tag:blogger.com,1999:blog-20533086500537622382024-02-20T12:38:36.089+00:00The WildlifewriterAn occasional blog about Natural HistoryWildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.comBlogger58125tag:blogger.com,1999:blog-2053308650053762238.post-2585320457626751932019-08-11T14:58:00.000+01:002019-08-11T14:58:04.014+01:00Foraging Study - 7L in Sussex<br />
<div class="western" style="margin-bottom: 0cm;">
<i><span style="font-family: "verdana" , sans-serif;">Here in the UK,
recreational angling is big business. In England, angling was
estimated to have put £STG 1.4bn into the local economy. (2018
figures) As a proportion of regional GDP, the amounts for Scotland,
Wales and Northern Ireland respectively are probably even higher than
that. And as the man said: 1.4 billion here, 1.4 billion there –
pretty soon you're talking real money. [1]</span></i></div>
<br />
<span style="font-family: "verdana" , sans-serif;"><br /></span>
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<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-QnkTXEoB010/XU8ol72yLRI/AAAAAAAACF8/c8N0Ecb5saoL4upQUnER1v-RJnbToLTkgCEwYBhgL/s1600/37withFish2.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><span style="font-family: "verdana" , sans-serif;"><img border="0" data-original-height="493" data-original-width="804" height="122" src="https://1.bp.blogspot.com/-QnkTXEoB010/XU8ol72yLRI/AAAAAAAACF8/c8N0Ecb5saoL4upQUnER1v-RJnbToLTkgCEwYBhgL/s200/37withFish2.jpg" width="200" /></span></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="color: #444444; font-family: "verdana" , sans-serif; font-size: xx-small;">7L's parent, 37, bringing in a fish</span></td></tr>
</tbody></table>
<span style="font-family: "verdana" , sans-serif;">Angling Clubs, and the
vast majority of their members, share our love of the countryside </span><span style="font-family: "verdana" , sans-serif;">and
the wild creatures who live there. But predatory birds will still
be predators and occasionally this can lead to some understandable
friction between anglers and conservation groups. </span><i style="font-family: Verdana, sans-serif;">“We can't
catch any fish in this lake because the ospreys (or cormorants,
herons, grebes, etc) have eaten them all!”</i><span style="font-family: "verdana" , sans-serif;"> It seems like a
fair complaint, but is it true?</span>
<br />
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<span style="font-family: "verdana" , sans-serif;"><br />
</span></div>
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<span style="font-family: "verdana" , sans-serif;">Let's do some
science...<br /><br />When a young female osprey, Blue 7L (Kielder N2,
2017) made her first return migration this year (2019), she arrived
back in Northumberland on the 25<sup>th</sup> May, took one look at
our horrible spring weather, and headed south again the following
day. Of course, as a non-breeding bird, 7L is free to wander
wherever she chooses and – after roaming around the south-east of
England for a while – she eventually settled in an area of Sussex;
about 50km south of London.</span></div>
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</span></div>
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<span style="font-family: "verdana" , sans-serif;">We were following 7L's
detailed movements using GPS tracking. And what she did in the
month that followed provided us with some very significant
information.</span></div>
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<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
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<a href="https://1.bp.blogspot.com/-sWINxh0Lvz0/XU8ooKSGMPI/AAAAAAAACGE/lSPSYlHxu7g3y1fGBaASu5RyvfRTuajZgCEwYBhgL/s1600/Study%2BArea18F.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><span style="font-family: "verdana" , sans-serif;"><img border="0" data-original-height="587" data-original-width="1084" height="173" src="https://1.bp.blogspot.com/-sWINxh0Lvz0/XU8ooKSGMPI/AAAAAAAACGE/lSPSYlHxu7g3y1fGBaASu5RyvfRTuajZgCEwYBhgL/s320/Study%2BArea18F.png" width="320" /></span></a></div>
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<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
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<span style="font-family: "verdana" , sans-serif;">But first, a question:
why was 7L down in the Weald of Sussex at all? It's not a place
where ospreys nest, although they are sometimes reported there on
passage. The countryside is wooded and rural but with many large
towns, and the busy area around Gatwick international airport is
close by.</span></div>
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<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
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<span style="font-family: "verdana" , sans-serif;">The answer is, of course, that she was there to eat.
Having just completed a long and arduous migration (for the
conditions in 2019 were far from helpful to northbound migrant
birds), 7L's first priority would be to feed up and recover physical
condition. Perhaps the absence of other ospreys competing for
resources was a plus point for her. This part of Sussex features a
couple of significant river systems, reservoirs large and small, and
- most importantly for our study – there are many small lakes and
ponds, often on private land and most (if not all) containing
fish.</span></div>
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<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">Sussex may not be popular with ospreys but it's well
supplied with angling clubs and venues for them. 7L soon found one of
the best of these – a series of stocked fishponds with a large
wooded area close at hand for roosting. It is identified as “Site
13” in our study.</span></div>
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<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
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<span style="font-family: "verdana" , sans-serif;">This single location
could have supplied all the food that a lone female osprey could
possibly need. All she had to do was stay there and collect a free
meal as and when necessary. But THAT isn't what happened...</span></div>
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</div>
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<span style="clear: left; display: inline; font-family: "verdana" , sans-serif; margin-bottom: 1em; margin-right: 1em;"></span></div>
<br />
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<a href="https://1.bp.blogspot.com/-PsvPcQqidz0/XU8onYpY70I/AAAAAAAACGA/6sa8aHzJ3C83aJFjLScqGKsb6nQasnTLgCEwYBhgL/s1600/Ardingly1.png" imageanchor="1" style="clear: left; display: inline !important; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" data-original-height="583" data-original-width="1116" height="166" src="https://1.bp.blogspot.com/-PsvPcQqidz0/XU8onYpY70I/AAAAAAAACGA/6sa8aHzJ3C83aJFjLScqGKsb6nQasnTLgCEwYBhgL/s320/Ardingly1.png" width="320" /></a><span style="font-family: "verdana" , sans-serif;">Over the next 30 days, 7L explored the whole area, seeking out every body of water - large or (preferably) small, she could locate. Following her GPS path, we had to locate them too – no simple task as several were not even marked on our larger-scale maps! Over the following weeks she visited these places multiple times, flying a total of 486 km during the period.</span></div>
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<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<div>
<span style="font-family: "verdana" , sans-serif;">Using the QGIS 3.8 geographical information system, I set up an analysis of these movements. The system selected a number of location “visits” according to set criteria which, after some experimentation, seemed to match the behaviour of a foraging bird. (It was not sufficient for 7L to have just flown over a given lake on her way to somewhere else.) You can find a detailed description of how this was done in the technical paper linked at the end of this article. [2]</span></div>
<div>
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<a href="https://1.bp.blogspot.com/-5YrlA8oCiz8/XU8omyttoMI/AAAAAAAACF4/-zvIQRmM4EojbX_fQqaTXHUXAL0H69tbACEwYBhgL/s1600/SF_Data_Redact.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><span style="font-family: "verdana" , sans-serif;"><img border="0" data-original-height="558" data-original-width="507" height="320" src="https://1.bp.blogspot.com/-5YrlA8oCiz8/XU8omyttoMI/AAAAAAAACF4/-zvIQRmM4EojbX_fQqaTXHUXAL0H69tbACEwYBhgL/s320/SF_Data_Redact.png" width="290" /></span></a><span style="font-family: "verdana" , sans-serif;">In all, 18 locations were selected and the total number of visits recorded for each. Although “Site 13” remained her favourite and she often returned there, it was certainly NOT her only resource for food. With a maximum distance between sites of some 20km, we conclude that these are not random movements, but rather that they demonstrate a structured (and probably highly-optimized) foraging strategy.</span></div>
<div>
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<span style="font-family: "verdana" , sans-serif;">Examination of inter-site flight paths supports something that we have always known about ospreys – they remember every single foraging location and, once fixed in the context of local landmarks, can fly back there by direct point-to-point routing – even in poor weather conditions with restricted visibility.</span></div>
<div>
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<span style="font-family: "verdana" , sans-serif;">We found that 7L showed a clear preference for smaller lakes and ponds. By contrast, the largest body of water in the area, Weir Wood Reservoir (a notable coarse angling venue), does not appear in our data table at all. She overflew it once, did not stop there, and never visited it again.</span></div>
</div>
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<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-2ysMwyoOtz4/XU8onUPf0JI/AAAAAAAACF8/232rIdQHjSYTvPTzvtSdBgmexZ_uUG4iACPcBGAYYCw/s1600/SF_3Dview3.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="768" data-original-width="1366" height="179" src="https://1.bp.blogspot.com/-2ysMwyoOtz4/XU8onUPf0JI/AAAAAAAACF8/232rIdQHjSYTvPTzvtSdBgmexZ_uUG4iACPcBGAYYCw/s320/SF_3Dview3.png" width="320" /></a></div>
<b><span style="font-family: "verdana" , sans-serif;">CONCLUSION</span></b></div>
<div>
<div>
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<span style="font-family: "verdana" , sans-serif;">Evolutionary Theory suggests that species such as ospreys should avoid exploiting a single food source, IF more than one such source is available. Computer modelling of predator-prey simulations also indicate that this ought to be true. BUT... obtaining confirmation of that behaviour in the wild is much more difficult than running a simulation. There are many extra variables – and the notorious English weather is only one of them.</span></div>
<div>
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<span style="font-family: "verdana" , sans-serif;">During her sojourn in Sussex, and thanks to high-resolution GPS tracking, 7L enabled us to observe her foraging behaviour in detail, and the results speak for themselves. Although some sites were favoured above others, ALL of them contributed to her overall food supply requirement and we suggest that the hypothesis is thereby proved...</span></div>
<div>
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<span style="font-family: "verdana" , sans-serif;">Ospreys do not over-exploit a single fishing location if other resources are available. In fact, they adopt an innate strategy which avoids doing this.</span></div>
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<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
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<b><span style="font-family: "verdana" , sans-serif;">Note on redactions</span></b></div>
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<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<span style="font-family: "verdana" , sans-serif;">Ospreys are a protected species under current UK environmental legislation.[3] They are sensitive to disturbance at all stages of their life cycle – including “well intentioned” disturbances by hobbyist photographers or over-enthusiastic birders. In cognizance of that, we implement a policy of withholding certain information in documents such as this.</span></div>
<div>
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<span style="font-family: "verdana" , sans-serif;">Since 7L is still active, and it is possible (even likely) that she may return to the study area in future seasons, we have removed specific references to named locations and held back or modified maps that may describe movements and roosting / foraging sites in too much detail. We hope that the reader will appreciate the necessity for this.</span></div>
<div>
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div>
<i><span style="font-family: "verdana" , sans-serif;">P. McMichael</span></i></div>
<div>
<i><span style="font-family: "verdana" , sans-serif;">J. Dailey</span></i></div>
<div>
<i><span style="font-family: "verdana" , sans-serif;">8th August 2019</span></i></div>
<div>
<br /></div>
<div>
<br /></div>
<div>
<span style="color: #4c1130;">Data and facilities from Forestry England and Kielder Water & Forest Park Development Trust </span></div>
<div>
<span style="color: #4c1130;">Additional mapping from OpenStreetmap.Org</span></div>
<div>
<span style="color: #4c1130;">Additional computing facilities from Sun Microsystems and Hewlett Packard Inc.</span></div>
<div>
<br /></div>
<div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "calibri" , sans-serif;"><sup>[1] </sup><a href="https://www.gov.uk/government/news/recreational-angling-puts-14bn-into-english-economy"><span style="font-size: x-small;">https://www.gov.uk/government/news/recreational-angling-puts-14bn-into-english-economy</span></a></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "calibri" , sans-serif; font-size: 13.3333px;">[2] </span><span style="font-size: x-small;"><span style="font-family: "calibri" , sans-serif;">"</span>Foraging
Behaviour of a 2<sup>nd</sup> Year Osprey (pandion haliaetus)
Surveyed by GPS Tracking." <a href="https://drive.google.com/file/d/16OZdlm1mDv6gSC5VeGycMe84ry5cPCxi/view?usp=sharing">https://drive.google.com/file/d/16OZdlm1mDv6gSC5VeGycMe84ry5cPCxi/view?usp=sharing</a></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "calibri" , sans-serif;"><span style="font-size: x-small;">[3] </span></span><a href="https://www.legislation.gov.uk/ukpga/1981/69/schedule/1" style="font-family: Calibri, sans-serif;"><span style="font-size: x-small;">https://www.legislation.gov.uk/ukpga/1981/69/schedule/1</span></a></div>
<div class="western">
<span style="font-family: "calibri" , sans-serif;">
</span>
</div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "calibri" , sans-serif;"><span style="font-size: 13.3333px;"><br /></span></span></div>
</div>
</div>
<br />Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com8tag:blogger.com,1999:blog-2053308650053762238.post-56793278742660139242019-06-23T16:14:00.000+01:002019-06-23T16:21:08.221+01:00Off The Grid... Aln/7L in Winter<br />
<div class="separator" style="clear: both; text-align: center;">
</div>
<div class="western" style="margin-bottom: 0cm;">
<b>THE STORY SO FAR.</b>..<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-Msh07d6OcYQ/XQ-U1o1p13I/AAAAAAAACE4/T7hDqHxND-EDK14o_L7ywTxUAceCl4W7ACEwYBhgL/s1600/n2-10-13-7l-touches-down.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" data-original-height="377" data-original-width="640" height="117" src="https://1.bp.blogspot.com/-Msh07d6OcYQ/XQ-U1o1p13I/AAAAAAAACE4/T7hDqHxND-EDK14o_L7ywTxUAceCl4W7ACEwYBhgL/s200/n2-10-13-7l-touches-down.png" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: xx-small;"><i>7L on her nest at Kielder</i></span></td></tr>
</tbody></table>
<br />
<span style="font-family: "verdana" , sans-serif;">We
had last heard from Aln (Blue 7L) on the 7<sup>th</sup> of November
2017, when her unusual, weather-dominated migration route through
Holland and Germany via the Swiss border with France and through
eastern Spain, appeared to have ended in the foothills of Morocco's
Atlas mountains.<br /><br />For days we waited, and then weeks. Hope
faded – other sub-adult ospreys had vanished from the tracking
charts at this point in their journey. But then...<br /><br />In late
December of that year, we received a fragment of data, indicating
that Aln was alive and wintering somewhere in northern Mauritania.
This “somewhere” was obviously out of range from the GSM cell
towers that carry our communications, and only when she wandered away
from it could we expect to hear more news.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "trebuchet ms" , sans-serif;"><br /></span></div>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-CLukPO64x80/XQ-N7srkzdI/AAAAAAAACEk/eaQCqBy4RZA5IwEmSY7sbSo1RUbbmDu3gCEwYBhgL/s1600/Heatmap1.png" imageanchor="1" style="clear: right; display: inline !important; margin-bottom: 1em; margin-left: auto; margin-right: auto; text-align: center;"><img border="0" data-original-height="826" data-original-width="1169" height="224" src="https://1.bp.blogspot.com/-CLukPO64x80/XQ-N7srkzdI/AAAAAAAACEk/eaQCqBy4RZA5IwEmSY7sbSo1RUbbmDu3gCEwYBhgL/s320/Heatmap1.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i>(Click any image for larger)</i></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">So we waited.
Eventually, in April 2019, </span><span style="font-family: "verdana" , sans-serif;">Aln embarked on her return migration. As her transmitter struggled to upload the mass of data it had
accumulated during the previous 18 months we began to fill in the
picture of where Aln had been, and what she had been doing. We don't
have all of it, and probably never will, but here – in the context
of one selected day – is part of Aln's story...</span></div>
<div>
<br /></div>
<div>
<span style="color: purple;">24<span style="font-size: 13.3333px;">th</span> Jun 2018, 04:03 UTC </span><i> Aln (Blue 7L) is an early riser. On her
first migration, back in Europe, this was an inclination. Here, in
midsummer of the Sahara Desert, it is a survival strategy...</i></div>
<div>
<i><br />Stars
still litter the sky but there is light enough to fly. Sunrise may
be be a couple of hours away but already the eastern horizon is a
narrow glaring band, like molten silver. Aln's favoured roost sites
are among the sand dunes of the desert interior. At night, these
locations are away from the chilly onshore breezes of the coastal
margin, and the scattered rocks store warmth from the previous day.
But she cannot be here when the sun rises and temperatures start to
soar. She heads west towards the nearest of several tidal lagoons,
four kilometres away.</i><br />
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-fTfDfKrRyno/XQ-N7XROSuI/AAAAAAAACEg/HzCo4WE7yUobahoflpUp9rFOqx6rvE5CwCEwYBhgL/s1600/arguin%2Bmap.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" data-original-height="718" data-original-width="500" height="320" src="https://1.bp.blogspot.com/-fTfDfKrRyno/XQ-N7XROSuI/AAAAAAAACEg/HzCo4WE7yUobahoflpUp9rFOqx6rvE5CwCEwYBhgL/s320/arguin%2Bmap.png" width="222" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">This is the Banc
d'Arguin National Park in Mauritania. It is a World Heritage site
and protected under the Ramsar treaty as a location of international
importance for biodiversity. By any standards, Aln has chosen a
remote and isolated location: there are no people here, no roads, no
fishing villages – even the Park staff, based at the southern part
of the reserve, face an arduous cross-country expedition of more than
300 km just to get here. It's an ephemeral terrain of tidal
channels, quicksands and ever-shifting dunes – because this “land”
really belongs to the Sea.</span><br />
<br />
<i><span style="color: purple;">06:27 – 07:20 UTC</span> Aln
arrives at the lagoon and waits there. The tide - now rising - has
not yet reached this far inland and the shallow water carries a thin
film of dust that has fallen during the night. The margins of the
pool show a white crust of evaporated salt. Although there are small
fish here, it would be hard for her to see them. </i><br />
<br />
<span style="font-family: "verdana" , sans-serif;">It is
the exact hour of sunrise. Although Aln is not conscious of it, the
sun's appearance feeds important information to the autonomous
centres of her brain: her internal “clock” registers that this
daybreak is slightly later than the one before, and the one before
that. Her innate navigational sense is also recalibrated by the time
difference, confirming that she knows exactly where she is.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-r_RlZQsbrs8/XQ-OAMzCz0I/AAAAAAAACEs/d1R0Tbyhvu4SIBSPp7dJrXZYGtxlagXMgCEwYBhgL/s1600/arguin_photo1.png" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" data-original-height="400" data-original-width="593" height="215" src="https://1.bp.blogspot.com/-r_RlZQsbrs8/XQ-OAMzCz0I/AAAAAAAACEs/d1R0Tbyhvu4SIBSPp7dJrXZYGtxlagXMgCEwYBhgL/s320/arguin_photo1.png" width="320" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<i><span style="color: purple;">08:39 UTC</span>
Aln flies west again another 6.5 km, crossing the southern lagoon to
a rocky promontory on the coast. From this vantage point she views
the area, taking in the activity of other birds and assessing the
state of the tide. It is still too early for fishing, as seawater
floods into the lagoons through a wide breach in the dune margin.
After a few minutes she takes wing again, moving north along the
shoreline...</i></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">Other birds... There
are many thousands here, in dozens of different species – but far
fewer than when Aln first arrived. The Gulf of Arguin is a unique
and vital location for migrating wildlife - one of the most
productive marine environments anywhere on the planet.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-7rMhRSzSIzA/XQ-N8sxQ2TI/AAAAAAAACEo/ozojQve_h4cZqwpXIqTi-Fh0jOehEJlkwCEwYBhgL/s1600/arguin_currents.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" data-original-height="527" data-original-width="477" height="320" src="https://1.bp.blogspot.com/-7rMhRSzSIzA/XQ-N8sxQ2TI/AAAAAAAACEo/ozojQve_h4cZqwpXIqTi-Fh0jOehEJlkwCEwYBhgL/s320/arguin_currents.png" width="289" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">Cold-water currents
carry organic nutrients up and over the edge of the African
continental shelf. Meanwhile, dust and sand blows onto the water
surface from the desert interior, bearing minerals such as phosphates
and nitrates. Fuelled by sunlight and fertilized from above AND
below, life explodes into action.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;"><br />
</span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">Microscopic plants -
the phytoplankton – multiply at such a rate that their biomass is
visible from space. They form the basis of a complex food web that
attracts all manner of marine creatures. Some - like the rare and
endangered Atlantic right whales - travel thousands of kilometres to
join the feast.
</span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-zHP4ffw8xo4/XQ-NykoTZqI/AAAAAAAACEo/5PLqyX83qf8HHg8cFhf2-Pwkqz1jgQldwCEwYBhgL/s1600/Arguin_plankton1.png" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" data-original-height="427" data-original-width="805" height="105" src="https://1.bp.blogspot.com/-zHP4ffw8xo4/XQ-NykoTZqI/AAAAAAAACEo/5PLqyX83qf8HHg8cFhf2-Pwkqz1jgQldwCEwYBhgL/s200/Arguin_plankton1.png" width="200" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<i><span style="color: purple;">09:07 UTC</span> Aln
arrives beside the wide and shallow flood channel that feeds the
northern lagoon, It is one of her routine fishing spots, but she
does not hunt as ospreys do in other places, on the wing. There is
no need. Instead, she stands on the side of a half-submerged sandbar
and watches for the fish as they struggle past in a few inches of
water. She is joined by a host of other piscivorous birds – all
taking advantage of this unusual situation...</i></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">The fish have been
betrayed. Normally a rising tide would provide deepening water to
protect them from the predators along the channel, but <i>here</i>
this seems to be happening far too slowly. While the tide attempts
to flood the land, the evaporative power of the desert sun is lifting
eighteen metric tons of water out of the lagoon EVERY MINUTE.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-s6r2fm2pI60/XQ-ODw80FPI/AAAAAAAACEw/jCba4fhOJic8ZTDmpoPiFRNqdfe2_IsJACEwYBhgL/s1600/Paths_overly1.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" data-original-height="826" data-original-width="1169" height="226" src="https://1.bp.blogspot.com/-s6r2fm2pI60/XQ-ODw80FPI/AAAAAAAACEw/jCba4fhOJic8ZTDmpoPiFRNqdfe2_IsJACEwYBhgL/s320/Paths_overly1.png" width="320" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<i><span style="color: purple;">13:59 UTC</span> Her hunger satisfied for the moment, Aln moves off to
the beach where it should be cooler. She perches on some sand bars
along the foreshore but it is still too hot for comfort. After a
while, she takes off and flies out to sea.</i></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">We have observed other
tracked ospreys doing the same thing. Flying is an extra way for
large birds to regulate the their body temperature. Veins and
arteries under the skin of their chests and flanks can be dilated,
allowing the slipstream to cool their blood directly.</span><span style="font-family: "trebuchet ms" , sans-serif;"> </span><br />
<br />
<i><span style="color: purple;">15:05
UTC </span>Aln has flown south 2.5km, arriving back at the cape where she
was this morning. Tracking data shows that it is one of her
favourite places – a rocky promontory that juts out into the sea.
Here, in a comfortable sea breeze, she can chose from many safe
perches that overlook the gulf. In front of her, migrating dolphins
race past, leaping and spinning clear of the water. 16 different
species of dolphin and porpoise have been identified at Arguin – a
record for the west African coast.</i></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<i><span style="color: purple;">17.28 UTC </span> “What
do wintering ospreys do all day?” From tracking and many field
observations, the answer seems to be – as little as possible for as
long as possible. Aln has remained at her vantage point for the last
two hours. This is not idleness – it is an exercise in inactivity
and the object is to conserve as much energy as possible.</i></div>
<div class="western" style="margin-bottom: 0cm;">
<i><br /></i></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-241WjAEXfj4/XQ-Nue9Me4I/AAAAAAAACEo/r7cM8kA7l54nBfJmEmr-vyBDl5KEPWQGgCEwYBhgL/s1600/Flyspeeds1.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="404" data-original-width="842" height="191" src="https://1.bp.blogspot.com/-241WjAEXfj4/XQ-Nue9Me4I/AAAAAAAACEo/r7cM8kA7l54nBfJmEmr-vyBDl5KEPWQGgCEwYBhgL/s400/Flyspeeds1.png" width="400" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">We have analysed
Aln/7L's flying speeds over the available recorded period and found
that they are much lower than those typically seen on migration. It
appears that wintering ospreys are in no hurry to do anything, and
this fits in with the whole pattern of instinctive energy
management.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm; page-break-before: always;">
<i><span style="color: purple;">19:40 UTC</span> Aln has arrived back at her roost site just as the sun
is setting. With minor variations, this will be her daily routine
for another ten months, until the time comes for her to return
northwards. By that time, she will have finished growing her new set
of adult feathers and will look very different in appearance. </i><br />
<i><br /></i></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-j8rU1vzXlns/XQ-N6wmqFFI/AAAAAAAACEc/NoRv50qXMLY7q-7-Bn0CVPMAQPqErCsoACEwYBhgL/s1600/Overview_Map7L_1.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="575" data-original-width="1086" height="211" src="https://1.bp.blogspot.com/-j8rU1vzXlns/XQ-N6wmqFFI/AAAAAAAACEc/NoRv50qXMLY7q-7-Bn0CVPMAQPqErCsoACEwYBhgL/s400/Overview_Map7L_1.png" width="400" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;">She has made her
wintering location work for her. To our human eyes, the Arguin coast
of Mauritania might look like a harsh and desolate landscape – but
it seems to be a good place for ospreys.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="color: purple;">Study period: 1-5-2018
to 19-4-2019 (354 days) Data points recorded : 175,451</span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<br /></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com9tag:blogger.com,1999:blog-2053308650053762238.post-8058937917503553662018-02-24T18:03:00.003+00:002018-06-05T11:59:58.528+01:00Catching the Worm<span style="font-size: large;"><b>Migration Forecasts 2018, #1</b></span><br />
<span style="color: blue; font-size: large;"><b><br /></b></span>
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://4.bp.blogspot.com/-WPYJW_mCaz8/WpGnEVyFNQI/AAAAAAAABnE/fYnV94obmhExmOQ6B74rWqUjcSt9VOsKACLcBGAs/s1600/UV_cumb_editx346.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="341" data-original-width="1243" height="108" src="https://4.bp.blogspot.com/-WPYJW_mCaz8/WpGnEVyFNQI/AAAAAAAABnE/fYnV94obmhExmOQ6B74rWqUjcSt9VOsKACLcBGAs/s400/UV_cumb_editx346.jpg" width="400" /></a></div>
<br />
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;"><i>Yep
– it's that time of year again....</i></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;">The
end of February is the period when some early birds are already
feeling the urge to leave behind the lazy sunshine of west Africa and
head for the wet and still-wintry north lands where they will breed. </span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;">A timely start to migration is important for all birds, and adult
ospreys in particular. Even though parts of northern Europe may
still be blanketed by snow, they can reach staging areas in Spain,
Portugal or France where food is available while they wait for Spring
to take a firmer hold.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span></div>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://2.bp.blogspot.com/-JtfTlKGlS9I/WpGmCf6nHDI/AAAAAAAABm4/IpKaZ3FoL1MGnfWjKEofl-3pbP9MZgpMACLcBGAs/s1600/forecast1_MODIS25Feb18_1.png" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><span style="font-family: Georgia, Times New Roman, serif;"><img border="0" data-original-height="616" data-original-width="943" height="209" src="https://2.bp.blogspot.com/-JtfTlKGlS9I/WpGmCf6nHDI/AAAAAAAABm4/IpKaZ3FoL1MGnfWjKEofl-3pbP9MZgpMACLcBGAs/s320/forecast1_MODIS25Feb18_1.png" width="320" /></span></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="color: #444444; font-family: Georgia, Times New Roman, serif;">Atlantic low-pressure weather system (c) McMichael 2018<br />(Click for full-size)</span></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;">This
time last year, these early migrators had a “goldilocks” window
to assist them – and this season, the exact same condition has
arisen again. This MODIS satellite picture shows a large circulating
low-pressure system in the eastern Atlantic. Winds on its
south-eastern quadrant are swinging round to create the long-distance
coastal flyway up through Mauritania and Morocco, while still leaving
open the Gibraltar straits, where wind speeds will be light.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;">Running
the forecast models a bit further on reveals that a second Atlantic
low is developing behind the first, and the models suggest that it
will be on the same track. Unlike 2017, this means that the
migration “window” could remain open for much longer – possibly
out to the 5<sup>th</sup> March and maybe even beyond that.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span></div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://3.bp.blogspot.com/-xXDwYPuXp5c/WpGmBkVlxMI/AAAAAAAABnA/cN-AByKrmDwshiHTpAKu0rco7I4YBPctwCEwYBhgL/s1600/forecast1_gfs25Feb18_1.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><span style="font-family: Georgia, Times New Roman, serif;"><img border="0" data-original-height="673" data-original-width="1151" height="233" src="https://3.bp.blogspot.com/-xXDwYPuXp5c/WpGmBkVlxMI/AAAAAAAABnA/cN-AByKrmDwshiHTpAKu0rco7I4YBPctwCEwYBhgL/s400/forecast1_gfs25Feb18_1.png" width="400" /></span></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-family: Georgia, Times New Roman, serif;">GFS model forecast for 25 Feb 2018. (Click for full-size)</span></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;">It
will be interesting to see what kind of reports come in from the key
watch points over the next ten days or so.</span></div>
<div class="separator" style="clear: both; text-align: center;">
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif;">-WlW</span></div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><img border="0" data-original-height="140" data-original-width="220" height="127" src="https://2.bp.blogspot.com/-q8Nl8x2jPxU/WpGnegVIvII/AAAAAAAABnM/BwQ5ox4dzI4pxBS00U4h7fqPADSe6JVYgCLcBGAs/s200/KFPartnerLOGO.png" style="margin-left: auto; margin-right: auto;" width="200" /></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><a href="http://www.visitkielder.com/play/discover/kielder-ospreys" target="_blank">Kielder Forest Partnership</a></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<br />Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com0tag:blogger.com,1999:blog-2053308650053762238.post-35157568250688796942017-07-08T06:17:00.000+01:002019-05-17T17:21:46.065+01:00Instrumental Solo<div align="LEFT" style="border-bottom: none; border-left: 1px solid rgb(221, 221, 221); border-right: 1px solid rgb(221, 221, 221); border-top: none; line-height: 0.48cm; margin-bottom: 0.32cm; padding: 0cm 0.32cm;">
<span style="color: #333333; font-family: "times" , "times new roman" , serif; font-size: large;">“<span style="font-family: "urbanoregular" , "helvetica" , "arial" , sans-serif;"><span style="font-size: 11pt;"><i>Why
don't ospreys migrate together as a family unit?” </i></span></span><span style="font-family: "urbanoregular" , "helvetica" , "arial" , sans-serif;"><span style="font-size: 11pt;">It
has almost assumed the status of Frequently Asked Question, and the
answer is simple...</span></span></span></div>
<div align="LEFT" style="border-bottom: none; border-left: 1px solid rgb(221, 221, 221); border-right: 1px solid rgb(221, 221, 221); border-top: none; line-height: 0.48cm; margin-bottom: 0.32cm; padding: 0cm 0.32cm;">
<span style="color: #333333; font-family: "times" , "times new roman" , serif; font-size: large;"><b>It's because they're ospreys...</b></span></div>
<div class="separator" style="clear: both; text-align: center;">
<span style="font-family: "times" , "times new roman" , serif; margin-left: 1em; margin-right: 1em;"><a href="https://3.bp.blogspot.com/-wIqZ-kvdbW4/WWBpY3UgOWI/AAAAAAAABYs/GYFw3SmN24wHUzCQQKqukf9p7lPawYD4wCEwYBhgL/s1600/UVFavePerch_BW350wjpg.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="305" data-original-width="694" height="140" src="https://3.bp.blogspot.com/-wIqZ-kvdbW4/WWBpY3UgOWI/AAAAAAAABYs/GYFw3SmN24wHUzCQQKqukf9p7lPawYD4wCEwYBhgL/s320/UVFavePerch_BW350wjpg.jpg" width="320" /></a></span></div>
<div class="separator" style="clear: both; text-align: left;">
<br /></div>
<div style="border-bottom: none; border-left: 1px solid rgb(221, 221, 221); border-right: 1px solid rgb(221, 221, 221); border-top: none; line-height: 0.48cm; margin-bottom: 0.32cm; padding: 0cm 0.32cm; text-align: left;">
<span style="color: #333333; font-family: Verdana, sans-serif; font-size: 11pt;">Some
other species of birds, for example geese and wild swans, do exactly
this: they travel from their breeding sites in family groups, with
the adults escorting their offspring to the wintering grounds,
hundreds or even thousands of miles distant. Without this guidance,
the fledglings would never know where to go. But in evolutionary
terms, the logistics of this have a very specific result: in a given
population and after only a few generations, all the birds end up
wintering in the same place! For grazing birds, this is a perfect
survival strategy. They assemble in a huge flock, food is not a
problem, (grass doesn't run away or hide) and there is safety in
numbers with many eyes watching for danger.</span><br />
<span style="font-family: Verdana, sans-serif;"><span style="color: #333333; font-size: 11pt;"><br /></span>
</span><a href="https://4.bp.blogspot.com/-jxagZXcOHBc/WWBpVrbtbxI/AAAAAAAABYo/qZcI8Ha03XYU_MoEzzv06I66dC21ep1CACEwYBhgL/s1600/FinnospsMigrPH1.jpg" imageanchor="1" style="clear: left; display: inline; float: left; margin-bottom: 1em; margin-right: 1em;"><span style="font-family: Verdana, sans-serif;"><img border="0" data-original-height="676" data-original-width="696" height="192" src="https://4.bp.blogspot.com/-jxagZXcOHBc/WWBpVrbtbxI/AAAAAAAABYo/qZcI8Ha03XYU_MoEzzv06I66dC21ep1CACEwYBhgL/s200/FinnospsMigrPH1.jpg" width="200" /></span></a><span style="font-family: Verdana, sans-serif;"><span style="color: #333333; font-size: 11pt;">But </span><span style="color: #333333; font-size: 11pt;">for ospreys and other species that hunt a limited resource, this system won't do at all. They are apex predators, not flocking geese...<br /><br />A
thousand ospreys arriving on a single African lake would exploit the
local fish supply at an unsustainable rate. To solve this problem,
evolution has arranged matters so that young ospreys have to find
their own way in Autumn. They are born with all the navigational
instincts needed to do this, but built into those same instincts is
sufficient positional uncertainty to ensure that the young birds are
dispersed over a wide wintering area. </span></span><br />
<span style="font-family: Verdana, sans-serif;"><span style="color: #333333; font-size: 11pt;"><br />This random end-point factor (referred to by scientists as a “stochastic element”) is one of the hidden secrets of osprey migration and is instrumental in forming many aspects of their post-juvenile behaviour.. It has evolved because a general dispersal in winter quarters gives the incoming youngsters a slightly better chance of survival as individuals. </span><span style="color: #333333; font-size: 11pt;"><br /><br />But where does this "randomness" in the selection of a final destination come from? That's a whole other story and really needs an article all of its own.<br /><br />Watch this space... ☺</span></span></div>
<span style="clear: left; float: left; font-family: "times" , "times new roman" , serif; margin-bottom: 1em; margin-right: 1em;"><span style="color: #333333; font-size: 11pt;"><br /></span></span>Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com5tag:blogger.com,1999:blog-2053308650053762238.post-87999388009192982802017-05-25T16:54:00.001+01:002019-08-26T14:26:57.913+01:00Wooden Headphones<div style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;"><i>... reckless behaviour affecting the conservation of a Schedule 1 protected species</i></span></div>
<div style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://2.bp.blogspot.com/-9u2eYIDd5BM/WSb0mkufNhI/AAAAAAAABU4/48NBYN1_NOUap4UUF3DdysukurdAkouNQCEw/s1600/empty_platform_12.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="312" data-original-width="800" height="155" src="https://2.bp.blogspot.com/-9u2eYIDd5BM/WSb0mkufNhI/AAAAAAAABU4/48NBYN1_NOUap4UUF3DdysukurdAkouNQCEw/s400/empty_platform_12.jpg" width="400" /></a></div>
<div style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;"><br /></span></div>
<div style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif;">During
the Pacific campaigns of World War II, native peoples on many small
islands (now generally called Melanesia) came into contact with the
products of Japanese, and then Western, technological culture for the
first time. Aircraft and ships brought stockpiles of military
support supplies – tinned food, construction material, tents and
clothing - to the islands, which the inhabitants referred to as
“Cargo” - the pidgin word for trade goods. Then, as mysteriously
as they had arrived, the service personnel accompanying this logistic
effort vanished again, as the fortune of war ebbed and flowed across
the region.</span></div>
<div style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif;"><br /></span></div>
<span style="font-family: Verdana, sans-serif;">The islanders weren't stupid. They knew the value
of the goods, but their own culture had no terms of reference to
explain how or why all this stuff had been produced and delivered.
The Ancestral Spirits had obviously meant the Cargo for <i>them</i> –
and if some had arrived, there must be more on the way...</span><br />
<span style="font-family: Verdana, sans-serif;"><span style="font-family: "verdana" , sans-serif;"><br /></span>
<span style="font-family: "verdana" , sans-serif;">They had observed the baffling rituals performed by the visitors, rituals which </span><span style="font-family: "verdana" , sans-serif;">preceded the arrival of Cargo. Soldiers marched up and down on the beaches. Others lit fires in straight parallel lines, and then spoke while wearing curious headdresses connected to grey boxes. The islanders reasoned, logically, that if they performed these same rituals correctly, more Cargo would be sent to them. THAT was how the world of the Spirits had always operated, was it not? </span></span><br />
<div style="margin: 0px;">
<span style="font-family: Verdana, sans-serif;"><br /></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-lt0qnFOU-i0/WSb0mtz79vI/AAAAAAAABVA/uIuCqfhobzIaqB7Ldlnj__lS7jNCYVDeQCEw/s1600/control_tower_1.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><span style="font-family: Verdana, sans-serif;"><img border="0" data-original-height="193" data-original-width="372" height="166" src="https://1.bp.blogspot.com/-lt0qnFOU-i0/WSb0mtz79vI/AAAAAAAABVA/uIuCqfhobzIaqB7Ldlnj__lS7jNCYVDeQCEw/s320/control_tower_1.png" width="320" /></span></a></div>
<span style="font-family: Verdana, sans-serif;">So
they marched up and down. They built “control towers” from
bamboo, and carved wooden headphones to use in them. They lit the
landing fires, and waited... But, far away, WWII had ended and the
aeroplanes never returned. These strange versions of religion
persisted in the South Pacific for many years, and anthropologists
coined a general term for them..</span><br />
<span style="font-family: Verdana, sans-serif;"> <b><i> </i></b></span><br />
<span style="font-family: Verdana, sans-serif;"><b><i>“Cargo Cults”</i></b></span><br />
<div>
<span style="font-family: Verdana, sans-serif;"><br /></span></div>
<div>
<span style="font-family: Verdana, sans-serif;">In
certain areas of Wales, and also in the Scottish borders, some
misguided people have been running around the countryside, putting up
platform poles for “osprey nests”. The rationale behind this
seems plain enough: in the past, ospreys have nested on artificial
platforms, therefore many more platforms means many more ospreys will
come. Simple, innit?</span></div>
<div>
<span style="font-family: Verdana, sans-serif;"><br /></span></div>
<div>
<span style="font-family: Verdana, sans-serif;">Except
that it's not that simple at all.</span></div>
<span style="font-family: Verdana, sans-serif;"><span style="font-family: Georgia, Times New Roman, serif;"><br /></span>
</span><br />
<div style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif;"><br /></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://4.bp.blogspot.com/-szcIXtIlsEU/WSb0mcR23lI/AAAAAAAABVA/ueSK2OmsBFMlRbd0z6rU3gL8OOQqIvNoACEw/s1600/RI_Nest_space_graph.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><span style="font-family: Verdana, sans-serif;"><img border="0" data-original-height="553" data-original-width="686" height="321" src="https://4.bp.blogspot.com/-szcIXtIlsEU/WSb0mcR23lI/AAAAAAAABVA/ueSK2OmsBFMlRbd0z6rU3gL8OOQqIvNoACEw/s400/RI_Nest_space_graph.png" width="400" /></span></a></div>
<div style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif;">We now know that population, dispersal, and nesting
dynamics in a recovering osprey population are complicated and have a
pattern of development that must be taken into account by any
responsible conservation plan. Low population density in a given
area means that male birds defend very large nesting territories.
Young birds returning to these areas disperse widely, often having to
cover hundreds of kilometres in their search for a mate and a
nest.</span></div>
<div style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif;"><br /></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://4.bp.blogspot.com/-68E6kc0jakc/WSb0nXtmCfI/AAAAAAAABVI/A8yki0zKyN4t6DtRMn8d9BfdNugJxdLoACEw/s1600/motny_narr250px.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><span style="font-family: Verdana, sans-serif;"><img border="0" data-original-height="864" data-original-width="250" height="320" src="https://4.bp.blogspot.com/-68E6kc0jakc/WSb0nXtmCfI/AAAAAAAABVI/A8yki0zKyN4t6DtRMn8d9BfdNugJxdLoACEw/s320/motny_narr250px.jpg" width="92" /></span></a></div>
<div style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif;">As (and if) the recovery proceeds normally, defended
territories become gradually smaller, pre-nuptial dispersal covers
shorter ranges, and more local nest sites are taken up. BUT it can
take several generations of birds for these changes to happen, and
ill-considered attempts to manipulate them cause problems: polygynous
nesting being only one of these.</span><br />
<span style="font-family: Verdana, sans-serif;"><span style="font-family: Georgia, Times New Roman, serif;"><br /></span>
<span style="font-family: Georgia, Times New Roman, serif;"><span style="font-family: "verdana" , sans-serif;">
</span>
</span></span><br />
<div style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif;">Unplanned
platform deployment isn't conservation at all – it's Cargo Cult
Ecology.</span></div>
</div>
<div style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif;"><br />
</span></div>
<div style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif;">These
hobbyist platform-builders do not understand the underlying processes
in a recovering osprey population. But unlike the rather smarter
south-sea islanders, they seem to have little or no interest in
finding out the real facts, preferring just to perform their Ritual
of Poles repeatedly in the superstitious hope that ospreys
will magically appear.</span></div>
<div style="margin-bottom: 0cm;">
<i><b><span style="font-family: Verdana, sans-serif;"><br />
</span></b></i></div>
<div style="margin-bottom: 0cm;">
<i><b><span style="font-family: Verdana, sans-serif;">The
only things missing are the wooden headphones.</span></b></i></div>
<div style="margin-bottom: 0cm;">
<span style="font-family: "georgia" , "times new roman" , serif;"><br /></span></div>
<div style="margin-bottom: 0cm;">
<span style="color: #660000; font-family: "georgia" , "times new roman" , serif;"><i><br /></i></span></div>
<div style="margin-bottom: 0cm;">
<span style="color: #660000; font-family: "verdana" , sans-serif;"><i><br /></i></span></div>
<div style="margin-bottom: 0cm;">
<span style="color: #660000; font-family: "verdana" , sans-serif;"><i>Source
material:</i></span></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm;">
“<span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><span style="color: #333333;"><i>Cargo
Cult: </i></span><span style="color: #333333;"><i>A
Melanesian Type-response to Culture Contact” </i></span><span style="color: #333333;">
T. Schwartz, UCSD, 1968</span></span></span></div>
<div style="margin-bottom: 0cm;">
“<i>A Review of Thirty-five Years of
Osprey (Pandion haliaetus) Nesting Data in Rhode Island”</i> E.S.
Walsh, University of Rhode Island, (2013)</div>
<div style="margin-bottom: 0cm;">
<a href="https://www.blogger.com/null" name="yui_3_14_1_1_1495723594330_208"></a>
<span style="color: #111111;">“<span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><i>The
demography of a newly established Osprey Pandion haliaetus population
in France” </i></span><span style="color: #111111;">Wahl,
Barbraud (2016)</span><span style="color: black;">
doi: 10.1111/ibi.12114 </span></span></span>
</div>
<div style="margin-bottom: 0cm;">
<span style="color: black;">“</span><span style="color: black;"><span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><span lang="en"><i>Distribution
pattern of an expanding Osprey </i></span></span></span></span><span style="color: black;"><span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><span lang="en">(</span></span></span></span><i><span style="color: black;"><span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><span lang="en"><span style="font-style: normal;">Pandion
haliaetus)</span></span></span></span></span></i><i><span style="color: black;"><span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><span lang="en"><i>
</i></span></span></span></span></i><span style="color: black;"><span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><span lang="en"><i>population
in a changing environment”</i></span></span></span></span><span style="color: black;"><span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><span lang="en">
Bai, ML., Schmidt, D., Gottschalk, E. et al. J Ornithol (2009) 150:
255. doi:10.1007/s10336-008-0345-3 </span></span></span></span>
</div>
<div style="margin-bottom: 0cm;">
<span style="color: #111111;">“<span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><span lang="en"><i>Density
dependence in a recovering osprey population: demographic and
behavioural processes”</i></span></span></span></span><span style="color: #111111;"><span style="font-family: "times new roman" , serif;"><span style="font-size: small;"><span lang="en">
Bretagbolle V, Mougeot F, Thibault J-C, (2008)
doi:10.1111/j.1365-2656.2008.01418.x</span></span></span></span></div>
<br />
<div lang="en" style="margin-bottom: 0cm;">
<br /></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com1tag:blogger.com,1999:blog-2053308650053762238.post-77819533530963123562017-01-24T17:49:00.000+00:002017-01-24T17:58:46.340+00:00TIME SENSITIVE<h3 style="margin-bottom: 0cm;">
Judging the onset of
migration</h3>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm; text-align: center;">
<a href="https://3.bp.blogspot.com/-PIB-yZb2lNc/WIeLUD3sJAI/AAAAAAAABGE/E5M5gFqb_rQeTrycfP-ghZ5ZzW31puPfQCLcB/s1600/daynight_anim.gif" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" height="200" src="https://3.bp.blogspot.com/-PIB-yZb2lNc/WIeLUD3sJAI/AAAAAAAABGE/E5M5gFqb_rQeTrycfP-ghZ5ZzW31puPfQCLcB/s200/daynight_anim.gif" width="200" /></a><i><span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: x-small;">“The time is out of joint—O cursèd
spite,<br />That ever I was born to set it right!<br />Nay, come, let's
go together. “</span></span></i></div>
<div style="text-align: center;">
<span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: x-small;">
</span></span></div>
<div style="margin-bottom: 0cm; text-align: center;">
<span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: x-small;"> Hamlet I,v</span></span></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm;">
<span style="font-size: small;">As we approach the end of January, it
might seem as if the time of Spring migration is still a long way off
– but in fact, things are already changing for our birds down in
Africa...</span></div>
<div style="margin-bottom: 0cm;">
<br />
<span style="font-size: small;">Long-distance migration is no trivial
matter. A bird cannot just one day decide <i>“It's probably time
that I was heading back to my summer nest. Better get moving.”</i>
Before THAT happens, birds must make physical preparations and some
of these preparations can take many weeks. In some species, feathers
must have been moulted and new ones grown out. And in almost all
species, substantial reserves of body fat have to be laid down as
fuel for the coming journey.</span><br />
<br />
<span style="font-size: small;">And then there's the matter of timing. </span></div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://2.bp.blogspot.com/-Lh0jF--JTBw/WIeLwtdo-3I/AAAAAAAABGI/hKhSP1c93q0bAZFO3J9MEFDr3jUarrZHQCLcB/s1600/sunpathx2_1.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="139" src="https://2.bp.blogspot.com/-Lh0jF--JTBw/WIeLwtdo-3I/AAAAAAAABGI/hKhSP1c93q0bAZFO3J9MEFDr3jUarrZHQCLcB/s200/sunpathx2_1.png" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: "times" , "times new roman" , serif;">"Sunpath" diagrams for 55ºN (left) and 15ºN (right) Click for larger</span></i></td></tr>
</tbody></table>
<div style="margin-bottom: 0cm;">
<span style="font-size: small;">It's been known for centuries that
migratory birds use changes in the length of day (“<a href="https://en.wikipedia.org/wiki/Photoperiodism">photoperiod</a>”)
as one primary factor in knowing when to migrate. The biological
mechanisms of how this works are complicated, and links to further
reading are given below. We now know that animals have internal
“clocks” that keep track of time over various periods, from daily
rhythms to the cycle of the whole year. These timers are moderated
by external factors including photoperiod, changes in temperature,
and even (in some cases) location-specific alterations in the flux of
Earth's magnetic field.</span></div>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-6SR2tGmgPEU/WIeQ7hf0GII/AAAAAAAABGc/x3-wJTIxb88NWB5FFokrNGMPpo0UgKy8wCLcB/s1600/CW_5F.jpg" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="247" src="https://1.bp.blogspot.com/-6SR2tGmgPEU/WIeQ7hf0GII/AAAAAAAABGc/x3-wJTIxb88NWB5FFokrNGMPpo0UgKy8wCLcB/s320/CW_5F.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;"><span style="font-family: "times" , "times new roman" , serif;">5F in the Gambia [C. Wood]</span></span></td></tr>
</tbody></table>
<div style="margin-bottom: 0cm;">
<span style="font-size: small;">In west Africa, the ospreys are already
measuring changes in the day length and the accuracy with which they
have to do this is rather surprising.</span><br />
<br />
<span style="font-size: small;">Here in northern Europe, even we humans
can notice that we have now passed the Winter solstice and the days
are growing longer again. </span><br />
<br />
<span style="font-size: small;">At a latitude of 54.5ºN (where this
author lives) each day is three minutes longer than the previous one
(19<sup>th</sup> Jan 2017) and the<i> rate </i>of this change is
increasing by about three to four seconds every day.</span></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://3.bp.blogspot.com/-UKJQ16HSOGM/WIeOaVfLdZI/AAAAAAAABGQ/l7cn9PQPECsgBvS0L_JUaYl_AHFJXgyHQCLcB/s1600/Carlisle_sungraph.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="121" src="https://3.bp.blogspot.com/-UKJQ16HSOGM/WIeOaVfLdZI/AAAAAAAABGQ/l7cn9PQPECsgBvS0L_JUaYl_AHFJXgyHQCLcB/s320/Carlisle_sungraph.jpg" width="320" /></a></div>
<span style="font-size: small;"></span><span style="font-size: small;">But nearer the equator - where our
birds are still consulting their ease in the Senegal sunshine - the
changes in day length are much less obvious. At 15ºN, each day is
only 30 seconds longer, and rate increase is less than one second per
day.</span><br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-nWKgJ5I2-CA/WIeOiig2YsI/AAAAAAAABGU/ada0jM_ny4IIPLIIBWiTTw-1mQwo4R3PwCLcB/s1600/Dakar_sungraph.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="121" src="https://1.bp.blogspot.com/-nWKgJ5I2-CA/WIeOiig2YsI/AAAAAAAABGU/ada0jM_ny4IIPLIIBWiTTw-1mQwo4R3PwCLcB/s320/Dakar_sungraph.jpg" width="320" /></a></div>
<div style="margin-bottom: 0cm;">
<span style="font-size: small;">This rate-of-change variable seems to
be very important to migratory birds. After all, some of them
(swallows, for example) are wintering south of the equator – where
the days are still getting <i>shorter</i>.</span><br />
<br />
<span style="font-size: small;">These changes are tracked by
photoreceptors deep in a part of the brain called the <a href="https://en.wikipedia.org/wiki/Suprachiasmatic_nucleus">hypothalamus</a>.
The exact details of what happens during this process are not fully
understood, but it appears that some kind of phase-comparison is
being made between the amount of light being detected, and the
“position” of the bird's internal circadian clock. We suspect
this because if <i>either</i> mechanism is interfered with, the bird
will no longer be able to evaluate photoperiod changes correctly.</span></div>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-PsdynjUNeCk/WIeSVV1rn7I/AAAAAAAABGk/nwIp-XY_6yIMc1CfyXadPTGV7E2IcO_8ACLcB/s1600/CW_osp2.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="200" src="https://4.bp.blogspot.com/-PsdynjUNeCk/WIeSVV1rn7I/AAAAAAAABGk/nwIp-XY_6yIMc1CfyXadPTGV7E2IcO_8ACLcB/s200/CW_osp2.jpg" width="175" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: x-small;">Unringed osprey, Gambia [C.Wood]</span></span></td></tr>
</tbody></table>
<div style="margin-bottom: 0cm;">
<br />
<span style="font-size: small;">But, however it all works, the fact is
that the faraway birds are already making their preparations to
return for the coming summer.
</span></div>
<span style="font-size: small;">
</span>
<br />
<div style="margin-bottom: 0cm;">
<span style="font-size: small;"><br /></span>
</div>
<span style="font-size: small;">
</span>
<br />
<div style="margin-bottom: 0cm;">
<span style="font-size: small;">I'm ready. Are you?</span></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm;">
<i><b><span style="font-size: small;"><span style="font-size: x-small;"><span style="font-family: "times" , "times new roman" , serif;">(Thanks to Chris Wood for the use of original photographs)</span></span></span></b></i></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm;">
<br /></div>
<div style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-size: x-small;"></span></span></div>
<div style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-size: x-small;"></span></span></div>
<div style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-size: x-small;"></span></span></div>
<div style="margin-bottom: 0cm;">
<span style="color: #660000;">[1] Evans, P. R. “Timing Mechanisms
and the Physiology of Bird Migration.” <i>Science Progress (1933-
)</i>, vol. 58, no. 230, 1970, pp. 263–275. www.jstor.org/stable/43419959.</span></div>
<div style="margin-bottom: 0cm;">
<span style="color: #660000;">[2] Ubuka T, Bentley GE, Tsutsui K.
Neuroendocrine regulation of gonadotropin secretion in seasonally
breeding birds. <i>Frontiers in Neuroscience</i>. 2013;7:38.
doi:10.3389/fnins.2013.00038.</span></div>
<span style="color: #660000;">
</span>
<br />
<div style="margin-bottom: 0cm;">
<br />
<span style="color: #660000;">[3] “Seasons of Life”
L.Kreitzman, R. Foster:</span>
<a href="https://www.amazon.co.uk/Seasons-Life-biological-rhythms-survive-ebook/dp/B003ZDNWNQ/ref=sr_1_1?s=books&ie=UTF8&qid=1485272609&sr=1-1&keywords=9781847652799">https://www.amazon.co.uk/Seasons-Life-biological-rhythms-survive-ebook/dp/B003ZDNWNQ/ref=sr_1_1?s=books&ie=UTF8&qid=1485272609&sr=1-1&keywords=9781847652799</a></div>
<div style="margin-bottom: 0cm;">
<br /></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com1tag:blogger.com,1999:blog-2053308650053762238.post-65463302367209365842016-10-13T18:15:00.000+01:002018-06-06T20:30:20.798+01:00Cast a Giant Shadow<span style="font-size: large;"><span style="color: blue;"><b><i><span style="font-family: "times" , "times new roman" , serif;"></span></i></b></span></span><br />
<div class="separator" style="clear: both; text-align: center;">
<span style="font-size: large;"><b><i><a href="https://4.bp.blogspot.com/-RxaaEfuQp68/V_--mXXxLWI/AAAAAAAABCM/O3LNP8Ds8coHVgw0teUm-KvBmr8I2lPcgCLcB/s1600/giant_shadow_1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="235" src="https://4.bp.blogspot.com/-RxaaEfuQp68/V_--mXXxLWI/AAAAAAAABCM/O3LNP8Ds8coHVgw0teUm-KvBmr8I2lPcgCLcB/s400/giant_shadow_1.jpg" width="400" /></a></i></b></span></div>
<br />
<br />
<div class="western" style="margin-bottom: 0cm;">
<a href="https://3.bp.blogspot.com/-2MeiNRQwSnc/V_-_rAV3rDI/AAAAAAAABCk/WYf0w0h5jgMHhZGDVw0uCqhG8uXcjxs0wCEw/s1600/UVstraightt_narrow1216_2.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" height="640" src="https://3.bp.blogspot.com/-2MeiNRQwSnc/V_-_rAV3rDI/AAAAAAAABCk/WYf0w0h5jgMHhZGDVw0uCqhG8uXcjxs0wCEw/s640/UVstraightt_narrow1216_2.jpg" width="202" /></a><span style="font-family: Georgia, Times New Roman, serif; font-size: small;">UV started his second
annual migration on the morning of the 10<sup>th</sup> of September
2016. It would be pleasant to recount that his departure was
accompanied by cheering crowds of well-wishers lining the route –
perhaps even that the traditional northern colliery band played a
stirring march, while fluttered cambric handkerchiefs and a silent
tear from the more demonstrative hearts sped him on his way.<br /><br />Of
course, it wasn't like that at all.<br /><br />Be they ever-so-famous in
Internet Land, individual ospreys perform this last act of the summer
season unobserved, for the most part. It marks the point where they
transition back to the solitary existence of winter, and only those
who are directly observed by scope or camera - or have a tracking
unit – will have the actual start of their migration recorded as
such.<br /><br />Perhaps it is as well that the trombones didn't turn
out, because UV's commencement was an inauspicious one.<br /><br />For
days, a succession of southerly and south-westerly gales had lashed
across the west of Great Britain. After the misery of a damp summer
almost devoid of sun, it was looking like one of the most turbulent
Septembers on record. But by the morning of the 10<sup>th</sup>, the
wind seemed to have changed direction for the better and many birds
began to move southwards towards the coast. The adventure was under
way. UV was off to Africa at last.<br /><br />He got as far as
Gloucestershire.<br /><br />Another series of weather fronts raced in,
bringing poor visibility and yet more adverse winds. From Kent to
Cornwall, thousands of migrant birds were already waiting for a
chance to cross into France. An inexperienced juvenile osprey might
have joined their ranks but UV is no longer a raw recruit. He paused
his migration at the River Severn and went fishing instead. The
weather finally relented on the morning of the 16<sup>th</sup>,
enabling our boy to make his move.<br /><br />And move, he certainly
did.</span></div>
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<a href="https://2.bp.blogspot.com/-ZayrtHn-4Og/V_-_C0o6kXI/AAAAAAAABCg/r3xGWIp_KCYDuvWpibjjF5JKEDFaQCH_QCEw/s1600/UV_speedrun1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><span style="font-family: Georgia, Times New Roman, serif;"><img border="0" height="203" src="https://2.bp.blogspot.com/-ZayrtHn-4Og/V_-_C0o6kXI/AAAAAAAABCg/r3xGWIp_KCYDuvWpibjjF5JKEDFaQCH_QCEw/s320/UV_speedrun1.jpg" width="320" /></span></a></div>
<div class="separator" style="clear: both; text-align: center;">
</div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Georgia, Times New Roman, serif; font-size: small;"><br />In the following nine hours he covered 373 km. Giving
Weymouth no more than a passing glance (as you would) he launched
himself out over the Channel. Off the island of Alderney, UV's (wind
assisted) flying speeds were some of the highest ever recorded by us
for a migrating osprey, peaking at 118 kph. <br /><br />The accompanying
maps show what happened next: UV 'cut the corner' through Brittany
and by afternoon the next day was out over the sea off Saint-Nazaire.
<br /><br />Adult ospreys have the same journey to undertake as
juveniles of their kind, but they have one major advantage: they know
where they are going and - perhaps even more importantly - they know
<i>how far</i> they have to go. A migrating adult has the option of
breaking the overall route into manageable sections, according to the
prevailing conditions and how much each bird has in the way of energy
reserves. This strategy is known as “staged migration”.<br /><br />UV
was aiming to stage at his favourite group of irrigation reservoirs –
the <i>barragens</i> of south-west Portugal, and he wasted little
time in reaching them by the 21<sup>st</sup>.</span><br />
<div class="separator" style="clear: both; text-align: center;">
<span style="font-family: Georgia, Times New Roman, serif; font-size: small;"><a href="https://2.bp.blogspot.com/-y5TkgUCgJpI/V__C6YpG8KI/AAAAAAAABCw/WJ8cv5qWe74jRQHgORKQDiH8xBQ3P_1QgCEw/s1600/UV19Sept2016_1200.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="174" src="https://2.bp.blogspot.com/-y5TkgUCgJpI/V__C6YpG8KI/AAAAAAAABCw/WJ8cv5qWe74jRQHgORKQDiH8xBQ3P_1QgCEw/s320/UV19Sept2016_1200.jpg" width="320" /></a></span></div>
<span style="font-family: Georgia, Times New Roman, serif; font-size: small;"><br />He may have got
an unpleasant surprise there. Diligent research by Joanna Dailey
found that serious drought conditions have been affecting this
region, and we believe that many of the dams had unusually low water
levels this year. This may have made fishing more difficult for UV
and we noted several unusual local movements at high altitudes, where
he seemed to be surveying the area and – perhaps – keeping an eye
on distant weather conditions with a view to moving on. (We have
withheld exact details of UV's foraging locations in Portugal for
protection reasons.)<br /><br />Whatever the fishing situation might have
been, it persuaded UV that two weeks in Portugal was enough. On 4<sup>th</sup>
October he was off again, following closely the same route that he
had taken in 2014, and this time his navigation was precise. After a
980+ km over-sea flight, his landfall in Morocco was only 14 km away
from the previous one.<br /><br />On that occasion, UV had staged at the
remote Gulf of Cintra in Western Sahara. So... would it be Cintra
again, this year? It would not. That weather-enforced break on the
River Severn had shifted UV's “refuelling” schedule just enough.
There were no more helpful tailwinds in the desert but, employing the
energy saving 'soar-and-glide' technique on plentiful thermals, UV
easily covered the remaining distance to northern Senegal.</span></div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://2.bp.blogspot.com/-LRyP_3l049c/V_--_1dlDDI/AAAAAAAABCg/kiWM3mOVM243Udlsutwhl80wVGOrNybywCEw/s1600/UC_Compare2014_2016_draft1.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><span style="font-family: Georgia, Times New Roman, serif;"><img border="0" height="192" src="https://2.bp.blogspot.com/-LRyP_3l049c/V_--_1dlDDI/AAAAAAAABCg/kiWM3mOVM243Udlsutwhl80wVGOrNybywCEw/s320/UC_Compare2014_2016_draft1.jpg" width="320" /></span></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;"><i><span style="font-family: Georgia, Times New Roman, serif;">UV Migration Map 2016<br />(2014 route in green)</span></i></span></td></tr>
</tbody></table>
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<span style="font-family: Georgia, Times New Roman, serif; font-size: small;"></span></div>
<span style="font-family: Georgia, Times New Roman, serif; font-size: small;">On
the evening of the 11<sup>th</sup>, as the shadows lengthened on the
Langue de Barbarie, UV slept in the very same roost tree that he had
used in February of this year.<br /><br />Because that's what they do.</span><br />
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span>
<span style="font-family: Georgia, Times New Roman, serif; font-size: small;">All of this information
comes from lines and dots and plots on a computer screen, the
shadow-tracks of the processed data. But Blue UV is no shadow. For
all our marvellous technology, we never forget that he is a living
creature. As we track their movements, so UV and his kin track our
understanding, waiting to see how we apply it to the benefit of all
their species.<br /><br />And that's one hell of a responsibility.</span><br />
<span style="font-size: small;">
</span>
<br />
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<a href="https://2.bp.blogspot.com/-G9Fg_ly8cUA/V_--lfOnDzI/AAAAAAAABCg/BiLJMGOW7SYag4aniN_v-UWgEtmVdb2qQCEw/s1600/migration_stats_1.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="157" src="https://2.bp.blogspot.com/-G9Fg_ly8cUA/V_--lfOnDzI/AAAAAAAABCg/BiLJMGOW7SYag4aniN_v-UWgEtmVdb2qQCEw/s400/migration_stats_1.png" width="400" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
-Wlw</div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
Kielder osprey blog: <a href="https://kielderospreys.wordpress.com/" target="_blank">https://kielderospreys.wordpress.com/</a></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com2tag:blogger.com,1999:blog-2053308650053762238.post-51644759419308980702016-09-04T17:59:00.005+01:002016-09-04T18:12:37.690+01:00Parent-offspring recognition in European ospreys<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">
</span></span></div>
<div class="western" style="font-style: normal; margin-bottom: 0cm;">
<span style="font-size: x-small;"><span style="color: blue;"><b>4th September 2016</b></span></span></div>
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<br /></div>
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<span style="color: blue;"><span style="font-size: medium;"><b><span style="font-size: small;"><i><span style="font-family: "times" , "times new roman" , serif;"> <span style="color: #20124d;">'How sharper than a serpent's tooth it is to have a thankless child' </span></span></i></span></b></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"> <span style="font-size: x-small;">[King Lear, I, iv]</span></span></span></div>
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<a href="https://3.bp.blogspot.com/--agrKgmVI0w/V8xEjAdurPI/AAAAAAAABAo/cLNwa9Rg99MC85FR0sR50EFO24Q5RLNPQCLcB/s1600/kielder_n2_2015_cc.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="155" src="https://3.bp.blogspot.com/--agrKgmVI0w/V8xEjAdurPI/AAAAAAAABAo/cLNwa9Rg99MC85FR0sR50EFO24Q5RLNPQCLcB/s400/kielder_n2_2015_cc.jpg" width="400" /></a></div>
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<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"></span></span></div>
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<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">Over the last couple of
weeks I've been inundated by literally two e-mails, both asking much the
same question:<span style="font-family: "verdana" , sans-serif;">-</span> </span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">“<i>Do parent ospreys
recognise their returning offspring from previous seasons?”</i></span></span></div>
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">
</span></span>
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">There is no simple
answer to this seemingly-straightforward issue. It seems clear that
many species of birds can recognize each other as individuals, once
they become acquainted. Of course, the term <a href="https://en.wikipedia.org/wiki/Kin_recognition">“kin-recognition”</a>
encompasses a whole raft of responses and behaviours, but in this
article I am going to focus on the question asked, which concerns
parent-offspring recognition.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">This has been proven in
birds that nest communally, and the selection pressures for this
ability to evolve in communal nesting are fairly obvious. Mechanisms
seem to include both vocal <i>and</i> visual recognition. Penguin
adults and chicks can locate each other – apparently by voice –
even in the noise and visual confusion of a busy colony. Beecher
(1988)<sup>[1]</sup> showed that bank swallows are able to do much
the same thing. Birds of prey, in contrast, tend to nest by
territory – but Alcaide et al (2007)<sup>[2]</sup> demonstrated
that these species (ospreys included) also carry the <a href="https://en.wikipedia.org/wiki/Major_histocompatibility_complex">MHC
gene sequence</a>, which had previously been associated with
kin-recognition ability (and lots of other things) in mammals.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">Ospreys, at best, nest
semi-communally and their migratory lifestyle complicates the issue
still further. Their young leave the nest at the end of summer, and
undergo a complete feather-replacement moult into adult plumage
before returning north to their natal regions. This means that a
returning youngster will be completely different in appearance,
calling into question the whole principle of visual identification by
the parent.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">All this stuff isn't
really getting us anywhere...</span></span></div>
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">
</span></span>
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://2.bp.blogspot.com/-pHqPz4ZNEt0/V8xEh2-F9iI/AAAAAAAABAk/XZayYd9ob9UjuJDaRhkl9MX7UUmcb78SQCLcB/s1600/UV1_paint_n.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="200" src="https://2.bp.blogspot.com/-pHqPz4ZNEt0/V8xEh2-F9iI/AAAAAAAABAk/XZayYd9ob9UjuJDaRhkl9MX7UUmcb78SQCLcB/s200/UV1_paint_n.jpg" width="132" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: xx-small;"><span style="font-family: "times" , "times new roman" , serif;">UV on the nest<br />(detail from original<br /> watercolour by <br />K Davies)</span></span></i></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">To find out more, I
turned to one of the most closely-observed young ospreys on the
planet. Yes, you've guessed it – it's UV again.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">UV is the trifecta for
this job: he has a high-visibility leg ring for ease of spotting, he
also has a satellite tracker for detailed following, and his parents'
nest at Kielder Forest Park is monitored by video recording cameras,
(courtesy of Forestry Commission England.) On 1st July 2016, he
landed on that nest while his mother was looking after this year's
brood of his siblings. Such an event – a year-two returnee
alighting on the natal nest and interacting directly with a parent –
is sufficiently rare that filmed recordings of it are almost
non-existent.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">But we got one.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
</div>
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<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"></span></span></div>
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<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"></span></span></div>
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<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"></span></span></div>
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"><span style="font-size: x-small;"><i><span style="font-family: "times" , "times new roman" , serif;"></span></i></span></span></span><br />
<div class="western" style="margin-bottom: 0cm; text-align: center;">
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"></span></span></div>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://vimeo.com/173143428" style="margin-left: auto; margin-right: auto;" target="_blank"><img alt="https://vimeo.com/173143428" border="0" height="178" src="https://1.bp.blogspot.com/-iK7q51-CG-s/V8xM43Sd7wI/AAAAAAAABBA/V1vBbU1vt10mdtsH3g54KTAFTgN45pZRwCLcB/s320/vidbutton_211.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><div class="separator" style="clear: both; text-align: center;">
</div>
<div class="western" style="margin-bottom: 0cm; text-align: center;">
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"><span style="font-size: x-small;"><i><span style="font-family: "times" , "times new roman" , serif;">Video (c) 2016 Forestry Commission England</span></i></span></span></span><br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"><span style="font-size: x-small;"><i><span style="font-family: "times" , "times new roman" , serif;">Used by permission</span></i></span></span></span><span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"><br /></span></span></div>
</td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">Short though it is, this sequence repays careful study.
We know from tracking data that UV approached the general nest area
from the south-west, and that he altered course directly towards it
when about 1000m up-range. The nest female sees him approach and
goes onto the nest to defend her brood. The chicks - of which there
are four - cannot yet fly at this date, so they crouch down in
response to the female's evident alarm-calls.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">UV makes several passes
over and round the nest, before finally landing on it. He alights
right on the edge, prepared to take the air again at a moment's
notice. His mother mantles and calls in protest at his temerity, and
within seconds she has chased him away.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">Is there any evidence
of “recognition” here? The answer has to be “no”... ALL the
birds involved behave and react in exactly the same way as if the
intruder had been an unrelated individual.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">Expert opinion is still
divided on the initial question. Some hold strictly to the view that
there is no parent-offspring recognition in European ospreys. Others
prefer the view that such recognition “ought” to have evolved,
and that there is no evidence to confirm its absence. A few (this
author included) suspect that the parent birds cannot recognise a
returning youngster, but that the <i>youngster</i> has some
instinctive awareness of the kinship<span style="font-family: "verdana" , sans-serif;">.</span></span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"><span style="font-family: "verdana" , sans-serif;"> </span>But all are agreed on
ONE thing: it doesn't make a blind bit of difference who is right!
The returnee is no more welcome at a nest site that any other osprey
would be, and the breeding adults would always react in <u>exactly</u>
the same way, offspring or not.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">So is that the end of
the story? Not quite.</span></span></div>
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">
</span></span>
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-hjBW2KGDhJk/V8xLbaqcMoI/AAAAAAAABA4/ilrypKXfnDw5AfzDZw9Q5FtuX8Mr3DYbACLcB/s1600/UV%2Bon%2BNest%2B2.jpg" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="112" src="https://4.bp.blogspot.com/-hjBW2KGDhJk/V8xLbaqcMoI/AAAAAAAABA4/ilrypKXfnDw5AfzDZw9Q5FtuX8Mr3DYbACLcB/s200/UV%2Bon%2BNest%2B2.jpg" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"><i><span style="font-size: xx-small;"><span style="font-family: "times" , "times new roman" , serif;">UV nabs a free meal at Nest 2<br />(Forestry Commission / J Dailey</span></span></i></span></span></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">For the remainder of
summer 2016, we continued to follow UV's activities. He remained
interested in Kielder Forest, and intruded at all the osprey nests
there on several different occasions. All the nests, that is, except
N1a... He only made one more return visit to his parent's nest and
did not land on it again. For most of the time, he maintained a
discreet distance from it while moving around the Park<span style="font-family: "verdana" , sans-serif;">.</span></span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;"><span style="font-family: "verdana" , sans-serif;"> </span>Does
this mean that UV is somehow aware that the parental nest is not a
proper place for him, whereas all the others are fair game for
investigation? I am not sure. Only the birds know these things for
certain.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">And they're still not telling. </span></span><br />
<br /><span style="color: purple;"><span style="font-size: x-small;"><span style="font-family: "arial" , "helvetica" , sans-serif;">[1] “<span lang="en">Kin
recognition in birds”: Beecher, M.D. </span><span lang="en"><i>Behav
Genet </i></span><span lang="en">(1988) 18: 465.
doi:10.1007/BF01065515</span> </span></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="color: purple;"><span style="font-size: x-small;"><span style="font-family: "arial" , "helvetica" , sans-serif;">[2] “<span lang="en">Characterization,
Polymorphism, and Evolution of MHC Class II B Genes in Birds of
Prey”: Alcaide, M., Edwards, S.V. & Negro, J.J. </span><span lang="en"><i>J
Mol Evol</i></span><span lang="en"> (2007) 65: 541.
doi:10.1007/s00239-007-9033-9 </span></span></span></span>
</div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com6tag:blogger.com,1999:blog-2053308650053762238.post-71725667867626798522016-08-13T14:27:00.001+01:002016-08-13T16:40:34.445+01:00COMMON CAUSE<div align="LEFT" class="western" style="margin-bottom: 0cm; margin-left: 2.47cm; margin-right: 3.54cm; text-decoration: none; text-indent: -0.03cm;">
<span style="font-family: "times" , "times new roman" , serif;"></span></div>
<div align="LEFT" class="western" style="margin-bottom: 0cm; margin-left: 2.47cm; margin-right: 3.54cm; text-decoration: none; text-indent: -0.03cm;">
<span style="font-family: "times" , "times new roman" , serif;">----------------------------------------------------</span></div>
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<span style="font-family: "times" , "times new roman" , serif;">“<i>When you have eliminated the impossible, whatever remains,
however improbable, must be the truth”</i></span><br />
<span style="font-size: x-small;">Arthur Conan Doyle </span><span style="font-size: x-small;"><i>The
Sign Of The Four</i></span><span style="font-size: x-small;"> (1890)</span></div>
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<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif; font-size: small;">Strange
things have been occurring at several of the monitored osprey sites,
this season. Unaccountable, worrying things that seem - on the face
of it - to be so far removed from the usual that they defy
explanation.</span></div>
<span style="font-size: small;">
</span>
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<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://3.bp.blogspot.com/-_BJ3TEdFVwo/V640kaNIpWI/AAAAAAAAA_E/ta1vI_ll5BMCqlavi1jqzajRiwQ4-umwACEw/s1600/ceri_fall_1.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="118" src="https://3.bp.blogspot.com/-_BJ3TEdFVwo/V640kaNIpWI/AAAAAAAAA_E/ta1vI_ll5BMCqlavi1jqzajRiwQ4-umwACEw/s200/ceri_fall_1.jpg" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><div class="western" style="margin-bottom: 0cm;">
<span style="color: #b45f06;"><span style="color: blue;"><span style="font-family: "times" , "times new roman" , serif;">17.7.2016 Fledgling Z0
“Cer<span style="font-family: "times" , "times new roman" , serif;">i"</span>
</span></span></span></div>
<span style="color: #b45f06;"><span style="color: blue;"><span style="font-family: "times" , "times new roman" , serif;">falls from a perch at
MWT Cors</span></span></span><br />
<span style="color: #b45f06;"><span style="color: blue;"><span style="font-family: "times" , "times new roman" , serif;">Dyfi and sustains
serious injuries<br />(Infra-red illumination)</span></span></span><br />
<span style="color: #b45f06;"><span style="color: blue;"><span style="font-family: "times" , "times new roman" , serif;">[Montgomery<span style="font-family: "times" , "times new roman" , serif;">shire WT]</span> </span></span></span></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif; font-size: small;">Fledgling
birds have been falling from their perches. Youngsters have appeared
to have difficulty in walking, holding their legs or talons at
strange angles. Some have flown and failed to return; others have
gone off their food, seemingly ill, only to recover later. One chick
(at MWT Cors Dyfi) has been so badly hurt that she went into
circulatory shock and died. And on social media and the forums,
everyone has been asking:-</span></div>
<span style="font-size: small;">
</span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif; font-size: small;"><i>What
the hell is going on?</i> </span></div>
<span style="font-size: small;">
</span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif; font-size: small;">These
are wild creatures and every moment of their lives is at hazard. Bad
things can and do happen to individuals, whether they are under
observation or not. It's Nature. Flying is an instinctive ability,
but the judgement of speed, distance and timing are not: these are
acquired skills and they have to be learned and </span><span style="font-family: "verdana" , sans-serif; font-size: small;"><span lang="en-GB">practised.
Young inexperienced birds sometimes have accidents, and the outcome
depends very much on chance and circumstances. Usually, they get
away with it unharmed – but not always. </span></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://2.bp.blogspot.com/-bvcUrtJOyJk/V640i0jht2I/AAAAAAAAA-4/h2phRRTqkXw_jSPhsE7HD3n0BSvjipyQwCEw/s1600/YA_kield_2015_wide.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="36" src="https://2.bp.blogspot.com/-bvcUrtJOyJk/V640i0jht2I/AAAAAAAAA-4/h2phRRTqkXw_jSPhsE7HD3n0BSvjipyQwCEw/s320/YA_kield_2015_wide.jpg" width="320" /></a></div>
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<span style="font-size: small;"></span>
</div>
<span style="font-family: "verdana" , sans-serif; font-size: small;">We
on the other hand are not wild birds. We are human beings and one of
our less-rational habits is to search for patterns in isolated
events, where often none exist. Psychologists even have a term for
it: <i>“apophenia”</i>. Scientists are trained to recognise this trait
in their own day-to day work, and to eliminate it in favour of
objectivity and rigour.</span><br />
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif; font-size: small;">There's
an app for that...</span></div>
<span style="font-size: small;">
</span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif; font-size: small;">Statistical
mathematics include a set of tools that can tell us whether the
frequency of an event (or series of events) is higher, lower, or the
same as might be expected to occur by chance. Numbers were crunched
and the answer came back: it was higher. Not by much, but
detectable.</span></div>
<span style="font-size: small;">
</span>
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<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-7vfaTMvo6JY/V640jWuuY0I/AAAAAAAAA_A/BQnwvNowsmAp6AKqKh8QoyevNd1PwKkbgCEw/s1600/W7Legbruise_1.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="114" src="https://1.bp.blogspot.com/-7vfaTMvo6JY/V640jWuuY0I/AAAAAAAAA_A/BQnwvNowsmAp6AKqKh8QoyevNd1PwKkbgCEw/s200/W7Legbruise_1.jpg" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><div class="western" style="margin-bottom: 0cm;">
<span style="color: #b45f06;"><i><span style="font-family: "times" , "times new roman" , serif;"><span style="color: blue;">30.7.2016 Osprey W7
sustains</span></span></i></span></div>
<span style="color: #b45f06;"><i><span style="font-family: "times" , "times new roman" , serif;"><span style="color: blue;">apparent grazing impact
injury.</span></span></i></span><br />
<span style="color: #b45f06;"><i><span style="font-family: "times" , "times new roman" , serif;"><span style="color: blue;">Close-up of bruising
and</span></span></i></span><br />
<span style="color: #b45f06;"><i><span style="font-family: "times" , "times new roman" , serif;"><span style="color: blue;">swollen leg
joint.</span></span></i></span><br />
<span style="color: #b45f06;"><i><span style="font-family: "times" , "times new roman" , serif;"><span style="color: blue;">[BGGW Glaslyn Wildlife]</span></span></i></span></td></tr>
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<br />
<span style="font-family: "verdana" , sans-serif; font-size: small;">This
begged the next question: could there be some underlying factor that
was affecting some of these birds but not others, even though the
incidents were happening in widely-separated nest locations and at
different times? Powerful minds (much more powerful than mine)
applied themselves to the problem. The 'usual suspects' were rounded
up: provisioning rates, environmental pollutants, fungal toxins...
one by one, they were eliminated from the inquiry. Exotic diseases
were invoked: could it be bird flu? Avian malaria? Trichomonosis?
Any of these can affect lower body function but they have other
symptoms, too, none of which seemed to be present.<br /><br />The leg
rings themselves were checked on, and checked on again. But all were
the same rings as had been used in previous years, made from the same
materials and fitted by the same teams. It wasn't the rings.<br /><br />Other
theories were suggested, from the mildly unlikely to the
just-plain-bonkers. Recessive gene mutations? <i>Nope</i>. Calcium
deficiency causing paralysis? <i>Can't be</i>. Short term
variations in the Earth's magnetic field? <i>Gimme a break</i>.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-family: "verdana" , sans-serif; font-size: small;">Perhaps
there IS no answer. Alternatively (and it's just another theory) the
answer might have been staring us in the face, all the time...</span></div>
<div class="separator" style="clear: both; text-align: center;">
</div>
<span style="font-size: small;"></span><span style="font-size: small;"></span><br />
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<div style="text-align: left;">
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-OtH_0E-SJC0/V68aYODXxMI/AAAAAAAAA_g/sCTKdGZrsqME5L39015bJmWSydEb8382ACEw/s1600/Y0_Kielder.JPG" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="153" src="https://4.bp.blogspot.com/-OtH_0E-SJC0/V68aYODXxMI/AAAAAAAAA_g/sCTKdGZrsqME5L39015bJmWSydEb8382ACEw/s200/Y0_Kielder.JPG" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><div style="margin-bottom: 0cm;">
<span style="color: blue;"><span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: x-small;"><i>Kielder
osprey Y0 fledged on 15<sup>th</sup> July, out of</i></span></span></span></div>
<div style="margin-bottom: 0cm;">
<span style="color: blue;"><span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: x-small;"><i>view
from the nest cameras. She did not return</i></span></span></span></div>
<div style="margin-bottom: 0cm;">
<span style="color: blue;"><span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: x-small;"><i>to
the nest after fledging. Current whereabouts</i></span></span></span></div>
<div style="margin-bottom: 0cm;">
<span style="color: blue;"><span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: x-small;"><i>unknown.
[Img: Paul McMichael]</i></span></span></span></div>
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</div>
<span style="font-family: "verdana" , sans-serif; font-size: small;"><span style="font-family: "verdana" , sans-serif;">I</span> was chatting with young Damien the other day. Damien is one of the
guys on the local red squirrel conservation survey, and he gets the
job of installing the higher-level trail cameras and bait trays.
Part biology student and part gibbon - with vocalizations to match –
Damien is not a happy arborealist these days. </span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-size: small;">“<span style="font-family: "verdana" , sans-serif;"><i>Duuude...
real gnarly climbing up there... like, slippy and slidey, y'know...
maaad dangerous...” </i> </span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: "verdana" , sans-serif;">And this is a bloke who will
happily hang from a branch by the crook of one elbow while thumbing
tweets into his mobile with the other hand. The boy's prehensile. If
Damien thinks that working up in the trees has suddenly become “mad
dangerous”, then something is amiss.</span></span></div>
<span style="font-size: small;"></span><br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-CzFnCwiM-Es/V640i8ABFcI/AAAAAAAAA-8/9A5Jg7gmQygliBs-XDjNmrGHrvlcSk8QACEw/s1600/June_rain.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="128" src="https://1.bp.blogspot.com/-CzFnCwiM-Es/V640i8ABFcI/AAAAAAAAA-8/9A5Jg7gmQygliBs-XDjNmrGHrvlcSk8QACEw/s320/June_rain.png" width="320" /></a><span style="font-size: small;"></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif; font-size: small;">My
UK readers will have noticed that, in 2016, the notorious British
Summer has been even less summery than usual. Rainfall - markedly in
the west and north - has produced totals for June that were 30%
higher than the moving average. The figures for July are not likely
to be much better. Cloud cover has been over 90% for almost 90% of
the days. These unsettled conditions have featured blustery winds,
variable in direction and gust strength. In technical terms, it's
been rubbish.</span></div>
<div class="western" style="margin-bottom: 0cm;">
<a href="https://4.bp.blogspot.com/-eNtPEbazF8Q/V640mvZsYII/AAAAAAAAA_I/AZMJ6lmawYgkKfHu7bY0fPJNCKVBU9iVQCEw/s1600/porthmadog_ran_2.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" height="201" src="https://4.bp.blogspot.com/-eNtPEbazF8Q/V640mvZsYII/AAAAAAAAA_I/AZMJ6lmawYgkKfHu7bY0fPJNCKVBU9iVQCEw/s320/porthmadog_ran_2.jpg" style="cursor: move;" width="320" /></a><br />
<br />
<span style="font-family: "verdana" , sans-serif; font-size: small;">What
effect might such unseasonably poor weather over such an extended
period have on the environment?<br /> </span><br />
<span style="font-family: "verdana" , sans-serif; font-size: small;">Wet and humid conditions are
ideal for growing the algae and moss that has </span></div>
<span style="font-family: "verdana" , sans-serif; font-size: small;">been troubling our
Damien. Branches of deadwood trees (exactly the ones that are
favoured by ospreys for perching) never get the chance to dry out,
making them slippery and even liable to breakages. Cloud cover
makes for poorer visibility, more difficult judgement of distance,
while gusting winds are the last thing that any fledgling bird needs
to encounter on its first experimental flights.</span><br />
<br />
<span style="font-family: "verdana" , sans-serif; font-size: small;">Any one of
these factors could cause a problem on its own – but put them all
together and they stack: generating a persistent and cumulative rise
in the accident rate that we start to notice.</span><br />
<br />
<span style="font-family: "verdana" , sans-serif; font-size: small;">And so we
mustn't give in to that seditious inclination of ours: that
everything that happens <b>must</b> have a single identifiable cause
and agent, so that we can hold someone or something “responsible”
before dashing off in pursuit of the next conspiracy. I find no
mysterious or even sinister forces at work here. There's an
underlying rough-and-tumble to any wild fledging season - and the
rougher it gets, the more tumbles it produces. In certain isolated
years, all the adverse factors combine in one relentless stream of
bad luck and unhappy accidents.</span><br />
<br />
<b><span style="color: #666666;"><span style="font-family: "verdana" , sans-serif; font-size: small;">I
blame the weather – but the weather didn't mean it. All these
incidents are still just Nature, doing that stuff She does.</span></span></b><br />
<br />
<div style="text-align: center;">
<b><span style="color: #666666;"><span style="font-family: "verdana" , sans-serif; font-size: small;">-------------------------------</span></span></b></div>
<br />
<b><span style="color: #666666;"><span style="font-family: "verdana" , sans-serif; font-size: small;"><span style="font-family: "trebuchet ms" , sans-serif;"><i><span style="color: #cc0000; font-size: x-small;">The views expressed in this article are those of the author himself, and are not intended to be<span style="font-family: "verdana" , sans-serif;"> </span>representative of any other organization or group.</span></i></span> </span></span></b>Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com1tag:blogger.com,1999:blog-2053308650053762238.post-2950534131647640302016-04-25T13:52:00.002+01:002016-10-12T21:14:07.687+01:00ELEVEN DEGREES WEST<div class="western" style="margin-bottom: 0cm;">
<span style="color: blue;"><i><b><span style="font-size: large;">UV and the passage of
the Sahara</span></b></i></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
So we think that UV has
commenced his return migration. His first challenge is to traverse
the western desert – a 2000 km flight to reach the straits of
Gibraltar. We tend to think of this as a hazardous route, and for us
it <i>would</i> be. But for birds – not so much...</div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://2.bp.blogspot.com/-rmP3G2pmKjo/Vx4R_0Z8n_I/AAAAAAAAA8c/Gh91gLTUjJE_xU075ZEjEO0Gpw2GGibbwCLcB/s1600/UV_Apr222-16_1.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="162" src="https://2.bp.blogspot.com/-rmP3G2pmKjo/Vx4R_0Z8n_I/AAAAAAAAA8c/Gh91gLTUjJE_xU075ZEjEO0Gpw2GGibbwCLcB/s320/UV_Apr222-16_1.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: xx-small;">22nd April 2016: UV sets out from Senegal, catching a few thermals on the way. (Data: Forestry Commission England) </span></span></td><td class="tr-caption" style="text-align: center;"></td><td class="tr-caption" style="text-align: center;"></td><td class="tr-caption" style="text-align: center;"><br /></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
</div>
<div class="western" style="margin-bottom: 0cm;">
There are few sizeable
predators, and even fewer that would be capable of taking on an
osprey. There are almost no invisible overhead cables to trap the
inattentive; no mad fat bastards with guns to shoot at them; no
speeding vehicles to collide with them. The skies are clear and
visibility is good. It's just a matter of flying.<br />
<br />
Of course
there are no fish and precious little water in a desert – but an
adult osprey in the early stages of migration does not require these
things. Before leaving Senegal, UV will have bulked up, laying down
fat reserves as fuel for the coming journey. And as he flies
northwards, his body deploys Evolution's secret weapon for
long-distance migration... “ß-oxidation.”<br />
<br />
This is part of
a three-stage process whereby lipids (stored fat) are converted into
energy to power UV's flight muscles. And as a by-product, metabolic
water is released at the cellular level. The numbers seem like a
conjuring trick: 110g of water is produced for each 100g of fat
consumed! (Okay, some other stuff is going on here as well, but
it's still a remarkable adaptation.)<br />
<br />
This biological miracle
is the key to long-distance bird migration: the longer and harder you
fly, the more water you get!</div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
-WlW</div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="color: #783f04;"><b>Further reading:<a href="http://ir.lib.uwo.ca/cgi/viewcontent.cgi?article=1941&context=etd" target="_blank">http://ir.lib.uwo.ca/cgi/viewcontent.cgi?article=1941&context=etd</a></b></span><br />
<br />
<br /></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com1tag:blogger.com,1999:blog-2053308650053762238.post-53132396476281708962016-03-10T15:16:00.003+00:002016-03-10T15:28:06.826+00:00Evidence for communal roosting of wintering European osprey Pandion haliaetus<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;"></span></span></div>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;">The breeding habits of
the European osprey have been well documented over the years but,
until comparatively recently, much less was known about their
lifestyle at winter quarters.</span></span><br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-KXmLqyIjq-I/VuF0fjMx-0I/AAAAAAAAA7s/dXepm0OEs84/s1600/UV%2B26th%2BAM%2BVJP_4249.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="179" src="https://1.bp.blogspot.com/-KXmLqyIjq-I/VuF0fjMx-0I/AAAAAAAAA7s/dXepm0OEs84/s320/UV%2B26th%2BAM%2BVJP_4249.JPG" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: xx-small;">UV on 26th Feb 2016 (Vic Paine)</span></span></i></td></tr>
</tbody></table>
<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;"> A combination of satellite tracking,
high-visibility rings, and diligent fieldwork from many sources has
increased our understanding of this seasonal behaviour, but much
remains to be discovered.</span></span><br />
<br />
<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;">In the last ten years,
bird tracking devices have used on-board GPS sensors in preference to
the much-less accurate doppler VHF system. This has allowed us to
observe specific movements during both day and night, and some
patterns have started to emerge...</span></span><br />
<br />
<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;">It had always been
thought that ospreys were mainly sedentary during the winter season,
keeping to a small activity area and seldom if ever leaving it until
the time for spring migration. But the higher levels of detail now
available has shown that this simplistic picture is not quite right.
Many ospreys - and especially those that forage along exposed beaches
and river systems - leave their hunting areas for the evening and
roost overnight at favourite spots further inland, often in the same
tree each night. Only where there are coastal or riparian “forests”
(such as mature mangrove) do they tend to remain in place.</span></span></div>
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<a href="https://2.bp.blogspot.com/-VfuwE3YQcbk/VuF0feFbLeI/AAAAAAAAA70/IG6BhbsWmTU/s1600/Ilpo_guinea_8th10thNov2015.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="157" src="https://2.bp.blogspot.com/-VfuwE3YQcbk/VuF0feFbLeI/AAAAAAAAA70/IG6BhbsWmTU/s320/Ilpo_guinea_8th10thNov2015.jpg" width="320" /></a></div>
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<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;">The
reasons for this behaviour are not difficult to deduce: beaches may
be warm and sunny during the day but chillier at night. Vegetation
tends to be low and sparse, so predation risk would be higher.
Evenings along river margins are when biting insects become most
active. </span></span></div>
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<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;">Many tracked ospreys, including “Ceulan” (Blue 3C
in 2012) have returned tracking info that demonstrates this
transference to off-area roosting. As I studied their various data
files over the years, I kept asking myself the same question: why is
this bird flying five, ten, even twenty kilometres to THIS roosting
tree? It must have flown past hundreds of other suitable trees to
get there – so what's so special about this particular roost?</span></span></div>
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<a href="https://3.bp.blogspot.com/-tbt-Sp60VPI/VuF0hergBDI/AAAAAAAAA70/rFwx4xB4_zU/s1600/ceulan_roost_oct2012.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="192" src="https://3.bp.blogspot.com/-tbt-Sp60VPI/VuF0hergBDI/AAAAAAAAA70/rFwx4xB4_zU/s320/ceulan_roost_oct2012.jpg" width="320" /></a></div>
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<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;">When Joanna Dailey, Pip
Rowe and Vic Paine visited NW Senegal <span style="font-size: xx-small;">[1]</span> in February 2016, I encouraged
them to pay special attention to the roost site(s) of osprey Blue UV
– a 2014 osprey from Kielder Water in Northumberland. This bird
was carrying a “second generation” GSM tracking device, so we
knew exactly where he was sleeping and were getting regular updates
each day on his diurnal movements. (I was under no illusions about
what I was asking of them: night falls very quickly at latitude
16ºN, and the west African bush is no place for newly-arrived white
folks to go wandering around in the dark.)</span></span><br />
<br />
<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;">Nonetheless, the group
DID manage to observe UV at his habitual roost site – and he wasn't
the only osprey using it! On successive mornings, they were able to
see several birds leave the area and fly westwards towards the
fish-rich Langue de Barbarie coastal strip. It was exactly what I
had hoped they would find. </span></span></div>
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<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-fEqKGLbWKWs/VuF0djXW_JI/AAAAAAAAA70/uMegMZPNmMk/s1600/UV%2B26th%2BAM%2BVJP_4236.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="247" src="https://1.bp.blogspot.com/-fEqKGLbWKWs/VuF0djXW_JI/AAAAAAAAA70/uMegMZPNmMk/s400/UV%2B26th%2BAM%2BVJP_4236.JPG" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-family: "times" , "times new roman" , serif;"><i><span style="font-size: xx-small;">UV leaves his favourite baobab tree in the early morning (Vic Paine)</span></i></span></td></tr>
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<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;">Later, Dirk
Vanhoecke (director of the Tougoupeul Project)<span style="font-size: xx-small;">[2]</span>, confirmed in
conversation with JD that his study group regularly see numbers of
ospreys - six or seven, typically - roosting together in the wooded
hinterland areas of NW Senegal. In this specific case, UV appeared to
be totally relaxed in the company of other ospreys: was seen preening
at perch and flying with them in the early mornings. The roost was
also occupied by other species, including red-billed hornbills <i>T.</i>
<i>erythrorhynchus
kempii.</i><br /><br />Although
large birds of prey do not form daytime flocks, communal or
semi-communal winter roosting has been observed in species such as
Bonelli's Eagle<span style="font-size: xx-small;">[3]</span> and Montague's Harrier. In recent years, migratory
lesser kestrel roosts of over to 20,000 individuals have been found
in west Africa <span style="font-size: xx-small;">[4]</span>. The survival benefits of communal roosting suggest
that ospreys should have evolved similar behaviour and, as their
overall population numbers slowly recover, we are beginning to see
evidence that this is so. </span></span></div>
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<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-duAik2fDLM0/VuF295lPtzI/AAAAAAAAA78/kUrWQOXFFY0/s1600/JD_ldeB_osprey_wide1.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="113" src="https://4.bp.blogspot.com/-duAik2fDLM0/VuF295lPtzI/AAAAAAAAA78/kUrWQOXFFY0/s400/JD_ldeB_osprey_wide1.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: "times" , "times new roman" , serif;"><span style="font-size: xx-small;">An osprey flies out over the Langue de Barbarie, Feb 2016 (Joanna Dailey)</span></span></i></td></tr>
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<span style="font-family: "verdana" , sans-serif;"><span style="font-size: small;"> </span></span><i><span style="font-family: "times new roman" , serif; font-size: small;">My
thanks to Vic Paine and JD for permission to use original photographs in
this article. </span><span style="font-size: small;"><i><span style="font-family: "times new roman" , serif;">
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<span style="color: #660000;"><span style="font-size: x-small;">[Links and sources...]</span></span></div>
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<span style="font-size: x-small;"><span style="color: #660000;">[1] Kielder Osprey blog</span>:<a href="https://kielderospreys.wordpress.com/2016/03/05/langue-de-barbarie-national-park-winter-home-for-uv-and-many-other-birds/" target="_blank">https://kielderospreys.wordpress.com/2016/03/05/langue-de-barbarie-national-park-winter-home-for-uv-and-many-other-birds/</a></span></div>
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<span style="font-size: x-small;"><span style="color: #660000;">[2] Project Tougoupeul </span>:
<a href="http://www.tougoupeul.be/">http://www.tougoupeul.be/</a></span></div>
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<span style="font-size: x-small;"><span style="color: #660000;">[3] <i>Communal Roosting
in Young Bonelli's Eagles (Aquila fasciata)</i>; Marcos<br />Moleón,
Jesús Bautista, and Agustín Madero (in Spanish)</span> :
<a href="http://dx.doi.org/10.3356/JRR-11-30.1">http://dx.doi.org/10.3356/JRR-11-30.1</a></span></div>
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<span style="font-size: x-small;">[4]<span style="color: #660000;"> Lesser Kestrel
roosting</span>: <a href="http://www.birdguides.com/webzine/article.asp?print=1&a=992">http://www.birdguides.com/webzine/article.asp?print=1&a=992</a></span></div>
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Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com1tag:blogger.com,1999:blog-2053308650053762238.post-47477773108789729812015-10-31T10:57:00.000+00:002015-10-31T11:16:31.782+00:00An Osprey For All Seasons – Blue 7H<div class="western" style="margin-bottom: 0cm;">
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<span style="font-family: Verdana, sans-serif;"><span style="font-size: small;">30<sup>th</sup>
October 2015</span></span></div>
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<span style="color: #0b5394;"><span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;">“<i>Bad
luck! If I’d any good luck to spare he could have some. I wish we
could all have good luck, all the time! I wish we had wings!”</i><span style="color: #444444;">
[Robert Bolt:<i>
A Man For all Seasons,</i>
II,i.] </span></span></span></span>
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<a href="http://2.bp.blogspot.com/-BW5paZbOUqY/VjPbq3USbdI/AAAAAAAAA6w/wy3z_JsUe_Y/s1600/activity_sheet_img1.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" height="200" src="http://2.bp.blogspot.com/-BW5paZbOUqY/VjPbq3USbdI/AAAAAAAAA6w/wy3z_JsUe_Y/s200/activity_sheet_img1.jpg" width="135" /></a><span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">We
call it the “activity counter” - and in the world of GPS-based
wildlife tracking, it can be a dreadful, portentous, doom-laden
thing.</span></span><br />
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">The
activity counter is a column of numbers in a data file. When a bird
or animal is being tracked, sensors in the PTT unit record any
movements between sample points, and increment this number at each
occurrence. An activity count that has NOT updated within a
significant span of time, brings on a feeling that is all
too-familiar to wildlife researchers:-</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">“<i>Oh,
no – not again...”</i> </span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">Whether
tracked or not, the population survival statistics for sub-adult
overwintering ospreys are – as with the young of many other
predator species – brutal and uncompromising. Fewer than one in
four ever return to their natal regions in northern Europe to breed.
It's unclear if this ratio is getting worse, but it certainly isn't
getting any better. Many adverse factors seem to be at work, and the
renowned conservationist Roy Dennis has estimated that some 60% of
losses are due to “human activities” - either directly (illegal
shooting and trapping, vehicle collisions, wire strikes, and so on)
or indirectly, through loss and conversion of habitat and potential
nest sites. Ospreys and other raptors that survive to breeding
maturity have one thing in common:<i> </i></span></span></div>
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<br />
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"><i>They
all had good luck, ALL of the time.</i></span></span></div>
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<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"><a href="http://2.bp.blogspot.com/-AxB8WbP-dbc/VjPbqXsf7oI/AAAAAAAAA60/ObgJ-oP9JfU/s1600/_7H.jdIMG_1461.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="325" src="http://2.bp.blogspot.com/-AxB8WbP-dbc/VjPbqXsf7oI/AAAAAAAAA60/ObgJ-oP9JfU/s400/_7H.jdIMG_1461.jpeg" width="400" /></a></span></span></div>
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<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">7H
was fledged at Kielder in 2014. She became special to <u>us</u>
in the way that these things always happen: though interest and
familiarity. But 7H was not a pet - she was and remained a wild,
free creature, doing exactly what her nature had inclined her to do.
In following her adventures and those of her kin from <a href="https://kielderospreys.wordpress.com/">Kielder
Forest</a>, we were able to learn more about this nature – and at a
level of detail that may not have been achieved before.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">We
observed her migration with bated breath, over land and sea. We
watched as she caught rides on passing ships (occasionally in the
wrong direction.) We saw her learn to catch fish, and how she became
gradually more proficient at this.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">7H was part of my <a href="http://thewildlifewriter.blogspot.co.uk/2014/11/slope-soaring-and-ridge-riding.html">study
into osprey flight strategies</a>, proving that even very young birds
of this species have an innate ability to exploit the winds and
thermal air currents, and to cover vast distances with the minimum
expenditure of energy. She contributed to new understanding of how
first-winter ospreys settle into a feeding territory, and interact
with others of their kind. She even taught us <a href="http://thewildlifewriter.blogspot.co.uk/2014/12/osprey-flight-speeds-are-females-faster.html">how
fast she could fly</a>, and how far... </span></span><br />
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<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"><a href="http://2.bp.blogspot.com/-8zhVGuHKvyE/VjPbyfI1Z5I/AAAAAAAAA7A/2WsYagJotfo/s1600/7H_overall_narrow.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" height="320" src="http://2.bp.blogspot.com/-8zhVGuHKvyE/VjPbyfI1Z5I/AAAAAAAAA7A/2WsYagJotfo/s320/7H_overall_narrow.jpg" width="241" /></a>On
her initial migration from Northumberland to Morocco, 7H traversed
5188 km. This might sound like a whole lot of flying to us, but her
activity in the year AFTER arrival puts this in a startlingly
different perceptive:</span></span><br />
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<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">In
the ensuing twelve months, 7H's total distance flown was an
<i>additional </i>9500 km – all carried out within about 40km of
her “home” roost locations. Clearly, our traditional view that
wintering ospreys “are mostly sedentary” does not reflect how
active they are on a day-to-day basis.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"> Because we were “with” 7H
through the full cycle of seasons, we are able to see how those
seasonal changes affected her foraging behaviour. We had
confirmation that ospreys will seek for, and use, different hunting
areas – even when there are more than adequate supplies in just one
of those areas. And in particular, a detailed analysis of 7H's
favoured perches and roost sites revealed that – to an osprey –
seclusion and the absence of human disturbance are much more
important than scenic views or epic landscapes.</span></span></div>
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<br />
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">So,
yes – we have learned a great deal from Blue 7H and this knowledge
is important for future conservation efforts. But 7H herself would
not have cared one jot for that. Instead, she spent 399 days in
Africa living the life that she was born into, free and wild. For
those 399 days it had appeared that she was doing everything right:
she had chosen a country where wildlife protection law is regarded
more seriously than it is in some less-civilized parts of the world –
such as Ireland, or Scotland.</span></span></div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
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<br />
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">Personally,
I choose not to grieve for the passing of 7H, but just to be thankful
for these many insights into her unique way of life. It has been a
rare privilege and one that I will not forget any time soon.</span></span></div>
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<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">-WlW </span></span></div>
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___________________________________________________________<br />
<br />
Joanna has written a valedictory article about 7H on the Kielder Ospreys blog, <a href="https://kielderospreys.wordpress.com/2015/10/31/7h-just-a-few-of-so-many-memories/" target="_blank">HERE</a></div>
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<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"><span style="color: #660000;"><span style="font-family: "Courier New",Courier,monospace;">Data provided courtesy of Forestry Commission England</span></span> </span></span></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com3tag:blogger.com,1999:blog-2053308650053762238.post-63905320310517057992015-09-18T12:07:00.000+01:002015-09-18T18:05:35.052+01:00"Side By Side" - FR4 and VY on migration<h2 class="western" style="margin-bottom: 0cm;">
<span style="color: blue;"><span style="background-color: white;"><b><span style="font-size: small;">VY and FR4 comparative
migration routes – Autumn 2015</span></b></span></span></h2>
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<a href="http://2.bp.blogspot.com/-KefcNDO8_7k/VfvzQPaxqzI/AAAAAAAAA5k/GxxxNO3VQrE/s1600/song1.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://2.bp.blogspot.com/-KefcNDO8_7k/VfvzQPaxqzI/AAAAAAAAA5k/GxxxNO3VQrE/s1600/song1.png" /></a></div>
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<tr><td style="text-align: center;"><a href="http://3.bp.blogspot.com/-3wYUILfyH4k/VfvuYAaD1-I/AAAAAAAAA5Q/w5XUALHfELQ/s1600/FR4%252BVY_BIG3.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="400" src="http://3.bp.blogspot.com/-3wYUILfyH4k/VfvuYAaD1-I/AAAAAAAAA5Q/w5XUALHfELQ/s400/FR4%252BVY_BIG3.jpg" width="255" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;">[Click for larger]</span></span></i></td></tr>
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<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">Of
the entire European population of ospreys, only a tiny proportion are</span></span></span></span></div>
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<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">satellite-tracked every season. Of these few, it's always found that
the juvenile birds follow very different migration paths – for
ospreys are solo travellers and each individual chooses its own
direction. But HOW do they choose these routes?</span></span></span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">This
year (2015), we are tracking Blue VY from nest site #1 at Kielder
Forest. She left “home” on 30</span></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><sup><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">th</span></sup></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">
August and made steady progress southwards, for conditions were
favourable at the time. Consistent breeze from the north and good
visibility are all that a young osprey requires at this time of year.</span></span></span></span></div>
<div align="LEFT" class="western" style="border: medium none; margin-bottom: 0cm; padding: 0cm;">
<br />
<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">By
coincidence, another (and unrelated) juvenile started its migration
at almost the same time: Blue FR4 from the <a href="http://scottishwildlifetrust.org.uk/visit/loch-of-the-lowes/">Scottish
Wildlife Trust</a> nest at Loch of the Lowes passed through 55ºN
about one day behind VY. The latter remained “in the lead” as
the birds made their way southwards – but FR4 gradually caught up,
helped in no small measure by VY's evident reluctance to make early
starts! By the time both were in southern Spain, their tracks had
converged both in distance </span></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><i><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">and</span></i></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">
time. At roost on the 8</span></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><sup><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">th</span></sup></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">
September, the pair were on identical courses and only 18 km apart.
(Even so, they remained totally unaware of each other's existence,
and would never meet.)</span></span></span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">This
unusual situation provides some insights into the factors that might
influence a juvenile's choices during migration, and the
most obvious of these is weather – or in this particular case,
the absence of it...</span></span></span></span></div>
<div align="LEFT" class="western" style="border: medium none; margin-bottom: 0cm; padding: 0cm;">
<br /></div>
<div align="LEFT" class="western" style="border: medium none; margin-bottom: 0cm; padding: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">With
such good conditions prevailing, both ospreys were able to follow
their instincts and take the most efficient and direct routes
southwards. This included the “inland” route over the western
Sahara desert, which is much shorter than following the African coast
as many previous tracked birds had done. However, such a “routine”
migration track did not cast much light on the behaviour of
individuals – until, that is, the youngsters made it into southern
Mauritania...</span></span></span></span></div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://2.bp.blogspot.com/-KBA9Rp-r0nw/VfvvBVJbKqI/AAAAAAAAA5Y/cmHx_YjJjqo/s1600/map_seneg1.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="196" src="http://2.bp.blogspot.com/-KBA9Rp-r0nw/VfvvBVJbKqI/AAAAAAAAA5Y/cmHx_YjJjqo/s400/map_seneg1.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;"><i>[Click for larger]</i></span></span></td></tr>
</tbody></table>
<div align="LEFT" class="western" style="border: medium none; margin-bottom: 0cm; padding: 0cm;">
<br />
<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">On
the afternoon of the 14</span></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><sup><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">th</span></sup></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">,
the young ospreys encountered their first real “problem” on this
migration. The rainy season in sub-Saharan Africa was well under way
– and that means variable monsoon winds out of the west and
slow-moving low pressure systems that track along the desert margins.
One such system was over the Senegal River valley as VY and FR4
arrived, and they found that the helpful northerly winds which had
borne them all the way from Britain were gone.</span></span></span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">As a result,
our ospreys had to adopt a different flight strategy and it was the
same in both cases – a course alteration SE to avoid the low
pressure with its rain and poor visibility. Once across the river,
they were able to turn south again, then back towards the SW on the
16</span></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><sup><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">th</span></sup></span></span><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">
as the weather conditions improved.</span></span></span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">It's
important to understand that the birds were not being “blown off
course” at any stage. They were simply adapting their route and
direction to take account of the winds and other conditions at the
time – just at all other times.</span></span></span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;">And this is why birds that
migrate independently can sometimes follow the same path.<span style="color: #783f04;"><span style="font-family: Times,"Times New Roman",serif;"> </span></span></span></span></span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="color: black; font-size: small;"><span style="text-decoration: none;"><span style="background: rgb(255, 255, 255) none repeat scroll 0% 0%;"><span style="color: #783f04;"><span style="font-family: Times,"Times New Roman",serif;">Images: Google Earth<br />VY Data: Forestry Commission England</span></span></span></span></span></span></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com2tag:blogger.com,1999:blog-2053308650053762238.post-35968634785672130162015-08-17T14:30:00.000+01:002015-08-17T14:56:57.457+01:00Dark Skies and Dancing Ospreys<div class="western" style="margin-bottom: 0cm;">
<a href="http://4.bp.blogspot.com/-TOMX7ivYhWo/VdHeg23zh5I/AAAAAAAAA2M/M6pDfaNVSN0/s1600/_030DSC_1332_RC.JPG" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" height="112" src="http://4.bp.blogspot.com/-TOMX7ivYhWo/VdHeg23zh5I/AAAAAAAAA2M/M6pDfaNVSN0/s200/_030DSC_1332_RC.JPG" width="200" /></a><span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;">“<i>Space is big. You
just won't believe how vastly, hugely, mind-bogglingly big it is. I
mean, you may think it's a long way down the road to the chemist's,
but that's just peanuts to space.”</i><span style="font-size: x-small;"> </span></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: x-small;">D. Adams – The
Hitch-Hiker's Guide To The Galaxy - Ch1</span></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif; font-size: small;">If
Douglas Adams had ever visited Kielder Forest, the same thought might
have occurred to him. At over 65,000 hectares, it's the largest
working forest in England. The main crop is sitka spruce, grown in
“fields” or forestry blocks on the nutrient-poor upland soil.</span><br />
<br />
<span style="font-family: Verdana, sans-serif; font-size: small;">It's
thirty years since I was last in Northumberland. I've arrived here
after a long drive from Worcestershire the previous day to meet with
Joanna, and also Martin the FC ornithologist. We gather at the
grandiose-sounding Kielder Castle – which is actually a rather
modest 18thC hunting lodge, now housing the small cafe where visitors
can view video feeds from the osprey nests. The nests themselves are
in remote areas of the forest, far off the tourist trails and cycling
paths around the reservoir.</span></div>
<span style="font-size: small;">
</span>
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://4.bp.blogspot.com/-WorqGBVW3X8/VdHewsULQWI/AAAAAAAAA2Y/HY4_szeJ-3A/s1600/Image%2B1_Kl.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="204" src="http://4.bp.blogspot.com/-WorqGBVW3X8/VdHewsULQWI/AAAAAAAAA2Y/HY4_szeJ-3A/s320/Image%2B1_Kl.jpg" width="320" /><i><span style="font-family: Times,"Times New Roman",serif;"></span></i></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: Times,"Times New Roman",serif;">Kielder Water from Leaplish</span></i></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif; font-size: small;">Today will be a special treat,
because Martin is going to accompany us up into those less-frequented
areas. After spending the winter doing interpretive desk-work on the
satellite tracking data, I need to get a better idea of the layout at
Kielder and how the various parts of the landscape relate to each
other. To this end, we have special dispensation to enter the working
forest roads – which are closed to the public due to the presence
of harvesting machinery and heavy transport in those areas.</span><br />
<br />
<span style="font-family: Verdana, sans-serif; font-size: small;">At
that moment someone else appears, unexpected and unannounced, and you
could knock me down with an osprey feather. It's Pip Rowe –
heroine of the “S<a href="https://kielderospreys.wordpress.com/2015/03/03/7h-near-azemmour-pip-rowes-five-star-report/">earch
for 7H</a>” in Morocco and all-round good person. There is a spare
seat so we pile our gear into Martin's 4x4 and set out for higher
ground...</span><br />
<br />
<span style="font-family: Verdana, sans-serif; font-size: small;">From
the upper track on Castle Hill, we can look down on the weir at
Bakethin and the viaduct. In the distance westward is the high
ground of <i>Black Fell</i> (379m). Last night, Joanna and I were
over there at the <a href="http://www.kielderobservatory.org/">Kielder
Observatory</a>, built in 2008 to take advantage of this
specially-protected “dark sky” zone. We were supposed to be
spotting auroras but cloudy conditions on the night prevented any
live viewing. However, Matt and the other staff astronomers put on a
good show of <i>“let's have a look at what you would have seen”</i>,
using existing photos and graphics on the big screen.</span></div>
<span style="font-size: small;">
</span>
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-MPF2WqJpp3k/VdHe2gObSfI/AAAAAAAAA2o/HeJ3v227cb0/s1600/Image_2_kl.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="163" src="http://1.bp.blogspot.com/-MPF2WqJpp3k/VdHe2gObSfI/AAAAAAAAA2o/HeJ3v227cb0/s400/Image_2_kl.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;">Kielder Observatory</span></span></td></tr>
</tbody></table>
<span style="font-size: small;"></span><span style="font-size: small;"></span><br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif; font-size: small;">It's
a remarkable and interesting facility, and well worth a visit if you
are in the area. </span><br />
<br />
<span style="font-family: Verdana, sans-serif; font-size: small;">During
my reverie, Martin and Joanna have been jumping in and out of the
vehicle to unlock and then secure various gates. We are now well
into the “operational” part of Kielder forest, with its patchwork
of plantation blocks in various stages of growth. This monoculture
of trees at identical heights is one reason that FC have erected
nesting platforms for the ospreys (who prefer to have a good view
over neighbouring timber) and also many dozens of nest boxes for the
forest's population of tawny owls. We can see one of the osprey
nests in the distance but there is no sign of the youngsters there.
Where are they? <br /><br />The track gains more altitude. A buzzard
drops from a branch and flies along the track just ahead of us,
giving a great close-up view before it wheels away down one of the
firebreaks. The road continues with many junctions and more gates,
and by now I have little remaining idea of where we are or where
we're going. It's all trees. Even the redoubtable Martin seems
slightly unsure of the route – this is a seldom-visited part of the
forest and only the rangers come up here on their regular rounds.<br /><br />We emerge under a
big and glowing sky into an area of clear-fell that has been
harvested and replanted. In suitable places, FC conservation staff
take advantage of the heavy machinery being deployed for planting, to
dig shallow ponds. These provide much-needed habitat for amphibians
and insect life, and a source of fresh water on the isolated uplands.
They also, it would seem, provide bathing places for young
ospreys... </span></div>
<div class="western" style="margin-bottom: 0cm;">
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-YuorIGv4Fyg/VdHex-Vu4BI/AAAAAAAAA2g/iC42EBozxSU/s1600/Image%2B_3_Kl.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" height="211" src="http://4.bp.blogspot.com/-YuorIGv4Fyg/VdHex-Vu4BI/AAAAAAAAA2g/iC42EBozxSU/s320/Image%2B_3_Kl.jpg" width="320" /></a></div>
<br />
<span style="font-family: Verdana, sans-serif; font-size: small;">Which
is exactly what the young ospreys are doing, right in front of us!</span><br />
<br />
<span style="font-family: Verdana, sans-serif; font-size: small;">The
pond itself would not win any awards in a <i>“Most Spectacular
Medium-sized Pond”</i> competition – but obviously it's a special
place for the birds, and now for us. With no disturbance from
walkers, no more forestry operations for the next twenty years or so,
and a clear view over the surrounding landscape, ospreys can gather
here in peace. As we watch, two juveniles dance and circle each
other on the far side of the slope, not a care in the world between
them. They are too far away to identify by leg rings, but the sight
is enthralling.</span><br />
<br />
<span style="font-family: Verdana, sans-serif; font-size: small;">Eventually
the birds depart in the late afternoon and it's time for us to move
on as well. I've been deliberately vague about exactly where the
Pond of the Ospreys is. It will always be a special place for
Joanna, Pip, Martin and me, but the location must remain secret - so
that next season another generation of birds can come here,
undisturbed, to bathe and circle and dance again under the dark and
shining skies of Kielder.</span><br />
<br />
<span style="font-family: Verdana, sans-serif; font-size: small;"> </span><span style="font-family: Verdana, sans-serif; font-size: small;">-Wlw <br />17th August 2015</span></div>
<div class="western" style="margin-bottom: 0cm;">
</div>
<span style="font-size: small;"></span><br />
<div class="separator" style="clear: both; text-align: center;">
</div>
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</div>
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<a href="http://3.bp.blogspot.com/-Fx-FZhhr7xI/VdHe94jcblI/AAAAAAAAA2w/nSVtEfSG9tw/s1600/Image_header_Kl.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="216" src="http://3.bp.blogspot.com/-Fx-FZhhr7xI/VdHe94jcblI/AAAAAAAAA2w/nSVtEfSG9tw/s400/Image_header_Kl.jpg" width="400" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana, sans-serif; font-size: small;"><br /></span></div>
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<span style="font-family: Verdana, sans-serif; font-size: small;"> </span>
</div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com5tag:blogger.com,1999:blog-2053308650053762238.post-14236921743711629202015-05-10T17:29:00.002+01:002015-05-11T16:34:21.049+01:00BATHTUB BLUES (And reds)<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: large;"><i>"In birds, the
emergency life-history stage is promoted by a release of the stress
hormone corticosterone. However, how corticosterone reduces the
expression of parental cares remains to be clarified. One hypothesis
is that the release of corticosterone may also affect prolactin
levels, a pituitary hormone widely involved in regulating parental
behaviours”</i></span> [1]</span></span></div>
<div class="western">
</div>
<div class="western">
</div>
<div class="western">
</div>
<div class="western">
<br />
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;"></span></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-GfcVIUQGMJ4/VU-F3plMzdI/AAAAAAAAAwU/T-Wtw3to4vQ/s1600/bath_headr_1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="213" src="http://2.bp.blogspot.com/-GfcVIUQGMJ4/VU-F3plMzdI/AAAAAAAAAwU/T-Wtw3to4vQ/s320/bath_headr_1.jpg" width="320" /></a></div>
<div class="western">
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;"><br />
</span></span></div>
<div class="western">
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">
</span></span></div>
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">
</span></span>
<br />
<div class="western">
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">Ospreys are a long-lived species and, as such,
their reproductive strategy is spread over multiple breeding seasons.
In this context, the survival of the adult female is paramount. When
something goes “wrong” during the early stages of nesting, female
birds have a physiological response to stress hormones that can
switch away from normal nesting behaviour, and back into a mode that
more resembles everyday life for a non-breeding individual. The
“wrongness” could be one single event – nest disturbance,
sudden reduction in food supply, prolonged bad weather, or desertion
by (or absence of) the paired male – or a number of events that,
taken together, add up to a “wrong” situation.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">This season (2015), we have seen several
high-profile examples of disrupted nesting behaviour – notably at
Glaslyn (non-return of the incumbent male) and at Loch Garten
(incumbent male apparently evicted by intruders.) Such events seem to be an integral part of the
osprey ecology, and have probably been occurring for many millions of
years. They are a necessary thing if the species is to continue in
its traditional breeding range</span></span></div>
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">
</span></span>
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-0h3Kz2Gmy5c/VU-F3XkTt4I/AAAAAAAAAwQ/RYkoRBhYT_E/s1600/cortisol_kittiwakes1.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="200" src="http://1.bp.blogspot.com/-0h3Kz2Gmy5c/VU-F3XkTt4I/AAAAAAAAAwQ/RYkoRBhYT_E/s200/cortisol_kittiwakes1.jpg" width="102" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;">From ref. [1]</span></span></i></td></tr>
</tbody></table>
<div class="western">
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">Scientists have discovered some of the mechanisms
that lead to this “emergency life-history stage”. One of them is
the effect of stress-related hormones such as corticosterones on
serum prolactin – the “parental behaviour” chemical that
normally takes precedence during nesting.</span></span></div>
<div class="western">
<br />
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">When prolactin levels crash in an emergency
life-history stage, we see the female apparently “abandoning” or
“ignoring” eggs, or even newly-hatched chicks. For human
observers, this action seems to be ethically and/or morally culpable,
but we must not look at it this way. The female bird has no choices
in the matter: without the correct circulating hormones to trigger
her behaviour, she no longer recognizes the eggs, does not know what
to do with them, has no interest in them at all. Nor has she really
“decided” to adopt a new strategy for her own survival or
breeding success at some later time – evolution has decided these
things for her.</span></span></div>
<div class="western">
<br />
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">This leaves the question of how the female's
behaviour can alter so quickly (or slowly) to take account of the
changing situation. To find out, we need to understand the way that
hormones are created in the body, how they are disposed of, and how
long these processes take – a branch of science called
<i>pharmokinetics</i>.</span></span><br />
<br /></div>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="http://2.bp.blogspot.com/-8amaMnwuX8U/VU-F3BmUZ5I/AAAAAAAAAwM/h6VZndCpyBM/s1600/LH_PRL_Graph1.jpg" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="193" src="http://2.bp.blogspot.com/-8amaMnwuX8U/VU-F3BmUZ5I/AAAAAAAAAwM/h6VZndCpyBM/s200/LH_PRL_Graph1.jpg" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;">From ref. [1]</span></span></i></td></tr>
</tbody></table>
<div class="western">
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">In birds, egg production seems to be associated
with a substance called luteinizing hormone (LH) – a glycoprotein
that is released from the pituitary gland. Parental behaviour
(incubation and caring for young), as we have already seen, is
promoted by prolactin. The relationship between LH and prolactin
levels in birds is very complicated, and both circulating factors are
affected by other substances. However, we do know that they can be
secreted in very large quantities, when conditions are
appropriate..</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">And it's this basal secretion rate that provides
the answer to rapid behavioural changes in birds, because NEITHER of
these hormones hang around in the bloodstream for very long. The
“serum half-life” of prolactin (the time taken for 50% of a given
quantity to be cleared) varies according to the size of the bird, but
in larger raptors seems to be around 40 minutes.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">Think of
trying to fill a bathtub when you have forgotten to put the plug in
the plughole. If the amount of water coming in through the taps is
greater than the outflow, then the bath will fill eventually – but
as soon as the filling rate slackens off, the water level will start
to fall again. Turn off the taps completely and the bath will empty
very rapidly.</span></span><br />
<br />
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">This is the way that seasonal reproductive
hormones act in birds: Only if the nesting situation is favourable in
most respects – and remains so, will hormones be maintained at the
correct level. The existence of an emergency life-history stage
is a remarkable adaptation. For birds in general, it is not an
incident of failure – it is one of the long-term secrets of their
success.
</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://4.bp.blogspot.com/-mnngNZZPD2g/VU-F4nGYPSI/AAAAAAAAAwo/Tds2hOg_t-Q/s1600/kielder%2Bnest2.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="150" src="http://4.bp.blogspot.com/-mnngNZZPD2g/VU-F4nGYPSI/AAAAAAAAAwo/Tds2hOg_t-Q/s200/kielder%2Bnest2.jpg" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;">(Click for larger)</span></span></i></td></tr>
</tbody></table>
SOURCES:</div>
<div class="western" style="margin-bottom: 0cm;">
<span style="color: #660000;"><br /><i>“</i><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><i><span style="font-weight: normal;">How
does corticosterone affect parental behaviour and reproductive
success? A study of prolactin in black-legged kittiwakes”</span></i></span></span><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span style="font-style: normal;"><span style="font-weight: normal;">
</span></span></span></span><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span style="font-style: normal;"><span style="font-weight: normal;">F
Angelier, C Clément-Chastel, J Welcker, G W Gabrielsen, O Chastel,
2009</span></span></span></span> </span><br />
<br />
<span style="color: #660000;">“<span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><i><span style="font-weight: normal;">Neural
Circuits Underlying Parental Behavior” </span></i></span></span><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span style="font-style: normal;"><span style="font-weight: normal;">C
Dulac, L A O’Connell, and Zheng Wu. 2014.<br />Neural Control of
Maternal and Paternal Behaviors. Science 345,no. 6198: 765–770.</span></span></span></span><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span style="font-style: normal;"><span style="font-weight: normal;"><br /></span></span></span></span></span></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com1tag:blogger.com,1999:blog-2053308650053762238.post-28854853216958406632015-03-20T11:55:00.000+00:002015-04-20T15:28:30.660+01:00Heatmap Haliaetus<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-s4Ln3zSAiVY/VQq5u1jZlNI/AAAAAAAAAts/9RMr87-hjSA/s1600/ebyt_vid1.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="http://4.bp.blogspot.com/-s4Ln3zSAiVY/VQq5u1jZlNI/AAAAAAAAAts/9RMr87-hjSA/s1600/ebyt_vid1.jpg" height="128" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: xx-small;"><a href="https://youtu.be/OMOGaugKpzs" target="_blank">Click for video</a></span></span></i></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;">“<i>Every single day
and every word you say,<br /> Every game you play, every night you
stay,</i></span></span><br />
<span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;"><i> I'll be watching
you...”</i></span></span></div>
<span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: small;"></span></span>
</div>
<span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm; margin-left: 1.25cm;">
<span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;"><span style="font-style: normal;"><b>Every Breath You Take</b></span> <i> </i></span></span></div>
<div class="western" style="margin-bottom: 0cm; margin-left: 1.25cm;">
<span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;"><i>Sumner, Matthew, Bogdanovic, Dusan</i>
(1983)</span></span></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span>
</div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">What did you do this
weekend? Did you perhaps go shopping, use an ATM machine, buy a
cinema ticket, hop on a bus or drive past a traffic monitoring
camera? Whatever you did, somewhere a computer programme made a
record of that stuff – the time, the place, the distance, the
amount - and added it to a list of similar activities that other
people did before you.</span></span></div>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">When <i>Every Breath You Take</i> was written, back in 1983, the song's sinister vision of
surveillance and obsessive control did not encompass today's reality.
The application of Geographic Information Systems (GIS) as a way of
drawing meaningful intelligence out of large data sets, outstrips
anything that could have been imagined by Sting, Orwell or Verne in
their day.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="http://1.bp.blogspot.com/-9BL5ndnAU_0/VQq33a_gHZI/AAAAAAAAAtM/3gqgxnyjDQI/s1600/7H_heatmap3.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://1.bp.blogspot.com/-9BL5ndnAU_0/VQq33a_gHZI/AAAAAAAAAtM/3gqgxnyjDQI/s1600/7H_heatmap3.jpg" height="217" width="400" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">The concept is simple enough: Take a list of data
points, each one having a set of attributes to be studied and some
form of location on a known co-ordinate system. The co-ordinates
might describe <i>any</i> kind of spatial relationship: from bacteria
growing on a Petri dish to aircraft flights on a map of the entire
globe, or anything in between. Once that lot has been loaded up, the
fun stuff can begin – for this is the kind of thing that computers
are very VERY good at...<br /> </span></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-NOQWUQ9R9Kc/VQq33_bBQ0I/AAAAAAAAAtQ/GJM1mFqmjjg/s1600/ronaldo1.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" src="http://2.bp.blogspot.com/-NOQWUQ9R9Kc/VQq33_bBQ0I/AAAAAAAAAtQ/GJM1mFqmjjg/s1600/ronaldo1.jpg" height="125" width="200" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"> Consider the movements of Premier League football
players on a soccer pitch. During the course of a single game, the
participants will roam all over the playing area. If we could obtain
a table of ALL these movements (and these days, we can) and plot them
on a diagram, the end result would just be a visually-confusing web
of tracks and changes of direction. But by subjecting the same data
to GIS processing, it becomes possible to highlight which zones the
defence occupied, and which paths were favoured by the attackers
before a goal was scored. Soccer, rugby and tennis coaches are now
using these techniques every day, as their players carry tiny
portable GPS dataloggers during training and competition. Even the
referees are not exempt from this post-match scrutiny, although some
of them are less than happy about such developments!</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">It's not all Big
Brother. GIS analysis is not just used to keep an eye on us: it can
benefit us and help to keep us safe. Architects use GIS to draw up
the fire-evacuation plans for large buildings. It optimises
ambulance routings and can predict areas of overcrowding in public
spaces.<br /><br />And these days, even ospreys are coming in for some
analysis...</span></span></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="http://2.bp.blogspot.com/--obupt2dWxg/VQq33Mxh4KI/AAAAAAAAAtI/NR2KG2CuQTg/s1600/qgis_desktop1.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="http://2.bp.blogspot.com/--obupt2dWxg/VQq33Mxh4KI/AAAAAAAAAtI/NR2KG2CuQTg/s1600/qgis_desktop1.jpg" height="112" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: xx-small;"><span style="font-family: Times,"Times New Roman",serif;">QGis "Brighton" 2.6 User interface</span></span></i></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"> I have installed a
software package called QGis 2.6. Like all GIS programmes, it is
horribly complicated and difficult to use, but the results are
rewarding. The image at the top of this page shows the activity
summary (known as a “heatmap”) for Kielder osprey Blue 7H during
her stay in Morocco. GIS allows us to select different ways of
looking at the data. It can measure how close one point is to
another, or how many occur within a specified area. In this case, we
told the computer to analyse only those points where the bird was
moving, and to keep a running total of how many there were in any
200-metre radius. The result above should give an indication of 7H's
favourite hunting areas, but puts less emphasis on places where she
was perched or roosting.<br /><br />We did a similar exercise on UV's
data during his stay in Portugal and obtained very accurate results.
(This heatmap has not been published because we expect him to use the
same locations in future seasons)</span></span></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">As far as we know,
no-one in Europe has used these tools to gain a picture of osprey
hunting behaviour before. As the material builds up, it is hoped
that the exercise will provide more insights and understanding of
this subject, as it is potentially important for conservation work.</span></span><br />
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="http://4.bp.blogspot.com/-S0_nNamN5bg/VQq33on9EzI/AAAAAAAAAtY/4xh174rrckE/s1600/7.JPG" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="http://4.bp.blogspot.com/-S0_nNamN5bg/VQq33on9EzI/AAAAAAAAAtY/4xh174rrckE/s1600/7.JPG" height="161" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;"><i>7H at Azemmour (Vic Paine)</i></span></span></td></tr>
</tbody></table>
<span style="font-size: large;"><span style="font-family: Times,"Times New Roman",serif;"><i>Every dive you make, </i></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: large;"><span style="font-family: Times,"Times New Roman",serif;"><i>Every fish you take,</i></span></span></div>
<span style="font-size: large;"><span style="font-family: Times,"Times New Roman",serif;"><i>I'll be watching
you...</i></span></span><br />
<span style="font-size: large;"><span style="font-family: Times,"Times New Roman",serif;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span>
</div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span>
</div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">-Wlw</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><i><span style="color: #660000;">[Data source: Forestry Commission England satellite tracking]</span></i></span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><span style="color: #660000;"><span style="color: black;">QGis Software Project: <span id="goog_2004118327"></span><a href="http://www2.qgis.org/en/site/about/index.html">http://www2.qgis.org/en/site/about/index.html</a></span></span><a href="https://www.blogger.com/"><i><span style="color: #660000;"> <span id="goog_2004118328"></span></span></i></a> </span></span></div>
<!-- Blogger automated replacement: "https://images-blogger-opensocial.googleusercontent.com/gadgets/proxy?url=http%3A%2F%2F4.bp.blogspot.com%2F-s4Ln3zSAiVY%2FVQq5u1jZlNI%2FAAAAAAAAAts%2F9RMr87-hjSA%2Fs1600%2Febyt_vid1.jpg&container=blogger&gadget=a&rewriteMime=image%2F*" with "https://4.bp.blogspot.com/-s4Ln3zSAiVY/VQq5u1jZlNI/AAAAAAAAAts/9RMr87-hjSA/s1600/ebyt_vid1.jpg" -->Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com2tag:blogger.com,1999:blog-2053308650053762238.post-52537339818561138922014-12-30T15:13:00.001+00:002014-12-30T16:48:44.090+00:00Osprey Flight Speeds: Are females faster than males?<div class="western" style="margin-bottom: 0cm;">
</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-P4HVFwqzaI8/VKK_T891XdI/AAAAAAAAAoo/mEmUBpL7KjU/s1600/mont_gles_chase1.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://1.bp.blogspot.com/-P4HVFwqzaI8/VKK_T891XdI/AAAAAAAAAoo/mEmUBpL7KjU/s1600/mont_gles_chase1.jpg" height="192" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: xx-small;"><span style="font-family: Times,"Times New Roman",serif;">Monty chases Glesni, Cors Dyfi 2013<br /> (Montgomeryshire Wildlife Trust)</span></span></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
</div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><b>Background</b> </span><br />
<br />
<span style="font-size: small;">“How fast can an
osprey fly?” is a topic that often comes up when these birds are
being discussed. There is, of course, no straightforward answer to
this question: all birds have a range of flying speeds, dependent on
what they happen to be doing at any given time. Nor is it easy to
establish a “maximum speed record” for any species of bird –
unless they are pursuing or being pursued, there is no real reason
for a bird to fly flat-out over any distance since this would be
wasteful of energy. Several attempts have been made to establish a
general rate of progress for migrating ospreys, using time intervals
between sightings, or by point-to-point measurements from satellite
tracking. None of these methods are really satisfactory, since there
are so many variables involved. The most significant contributions
have come from Sweden, by Alerstam, Kjellen and others. <span style="font-size: xx-small;">[1]</span> </span><br />
<br />
<span style="font-size: small;">In 2006, Lorna Shaw
(then an undergraduate at Nottingham University) conducted a study<span style="font-size: xx-small;">
[2]</span> of migrating ospreys <i>pandion haliaetus</i> using data from the
Rutland Water translocation project. Taking a sample of 21 individual
birds, Shaw concluded that female ospreys might fly slightly faster
than males, although the variance was not found to be statistically
significant. Given the state of tracking technology at the time,
this was to be expected.</span><br />
<br />
<span style="font-size: small;">We decided to address
this question by using a different approach. The latest generation of
GSM-type tracking devices record flight speeds directly, and at much
shorter intervals. We selected two first-time migrants (sub-adult),
one female and one male, that had been hatched (from different nests)
at Kielder Forest in the north of England. The birds are hereinafter
identified as “UV” (m) and “7H” (f) from their leg ring
codes. Both ospreys had been weighed and measured by Forestry
Commission staff during the ringing process; they were found to be in
good health and well-nourished, and so can be considered
representative of the general population.<b> </b></span><br />
<br />
<span style="font-size: small;"><b>Methods</b></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<span style="font-size: small;"><a href="http://2.bp.blogspot.com/-RP5Hwk7lGiA/VKK-dRFqhXI/AAAAAAAAAog/v-ifQXaKWLo/s1600/speeds_sidebar1.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="http://2.bp.blogspot.com/-RP5Hwk7lGiA/VKK-dRFqhXI/AAAAAAAAAog/v-ifQXaKWLo/s1600/speeds_sidebar1.jpg" height="320" width="119" /></a>The raw tracking data for both birds was obtained courtesy of
ForestryCommission England and loaded into a relational database
system. (See sidebar) The object of the study was to obtain an
analysis of ALL flight movements since fledging, from September to
end December 2014. The hypothesis that female ospreys generally fly
faster than males was to be tested. </span><br />
<br />
<span style="font-size: small;">The birds had been
fitted with 30gm GPS/GSM tracking units manufactured by Microwave
Technologies Inc, Mass, USA. These devices output animal movement
speeds in knots (nautical miles per hour) and this is the unit
referred to throughout, unless otherwise stated. Speeds are “over
the ground” in all cases. Since we were interested in <i>all</i>
aspects of flight – local, foraging, and migration – these were
not segregated. It is recognised that the wind is a major element in
bird flight and no attempt has been made to correct for its effects,
nor would this have been practicable.<b> </b></span><br />
<br />
<span style="font-size: small;"><b>Record selection and
processing</b> </span><br />
<br />
<span style="font-size: small;">The initial data tables
contained over 20,000 samples for each bird. We filtered out all
entries where the speed was recorded as zero, and also deleted all
records that were obvious GPS system or transmission errors. We also
removed any other entries that appeared to be anomalous for any
reason, even if the speeds shown were within acceptable criteria.
(In the case of 7H, I manually deleted those records where she was
known to be taking a lift on ships, as this might have given her an
unfair advantage!)</span><br />
<br />
<span style="font-size: small;">After this preparation,
the remaining sample sizes were: <i>n</i>=9192 for UV and <i>n</i>=9365
for 7H.</span><br />
<br />
<span style="font-size: small;">To summarise the data,
a range of speed classes were selected to construct a univariate
frequency distribution. The nominated range was 1-60 knots, in
increments of 5. (In the event, no valid speeds in excess of 55
knots were observed.) Corrections were made for the slightly
different overall sample sizes, and this resulted in the table and
graph following...</span><br />
<br />
<span style="font-size: small;">
</span><span style="font-size: small;">
</span><span style="font-size: small;">
</span><span style="font-size: small;">
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<tr valign="TOP">
<th width="20%"><div class="western">
<span style="font-size: small;">Speed Classes (Kts)</span></div>
</th>
<th width="20%"><div class="western">
<span style="font-size: small;">Range UV</span></div>
</th>
<th width="20%"><div class="western">
<span style="font-size: small;">Range 7H</span></div>
</th>
<th width="20%"><div class="western">
<span style="font-size: small;">% Range UV</span></div>
</th>
<th width="20%"><div class="western">
<span style="font-size: small;">% Range 7H</span></div>
</th>
</tr>
</thead>
<tbody>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">1-5</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">243</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">255</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2.644</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2.723</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">5-10</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">597</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">615</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">6.495</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">6.567</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">10-15</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">1740</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">1792</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">18.930</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">19.135</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">15-20</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2208</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2248</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">24.021</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">24.004</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">20-25</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2274</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2296</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">24.739</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">24.517</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">25-30</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">1201</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">1222</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">13.066</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">13.049</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">30-35</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">634</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">641</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">6.897</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">6.845</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">35-40</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">209</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">210</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2.274</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2.242</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">40-45</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">74</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">74</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">0.805</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">0.790</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">45-50</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">10</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">10</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">0.109</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">0.107</span></div>
</td>
</tr>
<tr valign="TOP">
<td width="20%"><div align="CENTER" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">50-55</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">2</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">0.022</span></div>
</td>
<td width="20%"><div align="RIGHT" class="western">
<span style="font-family: Verdana, sans-serif; font-size: small;">0.021</span></div>
</td>
</tr>
</tbody>
</table>
<span style="font-size: small;">
</span><br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://2.bp.blogspot.com/-j6yoz3midF0/VKK-bbLiThI/AAAAAAAAAoY/IbdTjD0w9_Q/s1600/7HUV_speedchart.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://2.bp.blogspot.com/-j6yoz3midF0/VKK-bbLiThI/AAAAAAAAAoY/IbdTjD0w9_Q/s1600/7HUV_speedchart.jpg" height="232" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: Times,"Times New Roman",serif;">[Click for larger]</span></i></td></tr>
</tbody></table>
<div class="separator" style="clear: both; text-align: center;">
<span style="font-size: small;"></span></div>
<span style="font-size: small;"></span><br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><b>Conclusion</b> </span><br />
<br />
<span style="font-size: small;">In their daily
behaviour, the most common flying speed for young ospreys is in the
range 15-25 knots (28-46 Km/h). Velocities higher than this are not
uncommon, and wind assistance during migratory passages is probably a
major factor.</span><br />
<br />
<span style="font-size: small;">Although the male bird
appeared to demonstrate a preference for slightly higher speeds in
the medium range and lower speeds elsewhere, an ANOVA variance
analysis of the data indicates that this is not statistically
significant. We conclude that there is no effective difference in
flying speeds between the sexes.</span></div>
<br />
<span style="font-size: small;">The birds studied had
hatched in the same natal area and commenced their annual migration
within a few days of each other. Although they took different routes
southwards, and had long stopovers at different locations, these
routes and locations (UV in SW Portugal and 7H in NW Morocco) would
have had generally similar weather patterns and wind conditions
during the period being studied. For this reason, the comparisons
between the data sets are probably as valid as could reasonably be
expected in the wild.</span><br />
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="color: #660000;"><span style="font-size: small;">Links:</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="color: #660000;"><span style="font-size: small;"><span style="font-size: x-small;">[1]</span> "</span><i><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: x-small;">Factors affecting the
autumn migration of Ospreys" </span></span></i><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: x-small;">Shaw L, Rutland water website: <a href="http://www.zen88810.zen.co.uk/ROspreys%20site/Satellite%20analysis.htm">http://www.zen88810.zen.co.uk/ROspreys%20site/Satellite%20analysis.htm</a></span></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="color: #660000;"><i><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: x-small;">[2] </span></span></i><span style="font-family: Arial;"><i><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: x-small;">"Timing and speed of
migration in male, female and juvenile ospreys Pandion
haliaetus between Sweden and Africa as revealed by
field observations, radar and satellite tracking."</span></span></i>
<span style="font-size: x-small;"> </span></span><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: x-small;">Kjellen
N, Hake M, & Alerstam T. (2001 Journal of Avian Biology <b>32</b>,<b>
</b>57-67.</span></span></span></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com3tag:blogger.com,1999:blog-2053308650053762238.post-30088418693613492242014-12-23T17:35:00.000+00:002014-12-23T17:46:53.039+00:00Sebkhets of the Sahara<div class="western" style="margin-bottom: 0cm;">
<b><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">Geography Lessons from
Ospreys #438</span></span></b></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: small;"><i>Location: Assouerd
Province, Western Sahara</i></span></span><br />
<br />
</div>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="http://resources.waza.org/files/images/w(415)h(252)c(1)q(90)/eacd5bdb9cfde9b80aeefac7b138ba1c.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="http://resources.waza.org/files/images/w(415)h(252)c(1)q(90)/eacd5bdb9cfde9b80aeefac7b138ba1c.jpg" height="194" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;">Dama Gazelles (Image: W.A.Z.A. Conservation)</span></span></i></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">The western coastal
margin of the Sahara Desert is a region with almost no rainfall. To
our eyes, it appears desolate and lifeless – and yet there IS
wildlife here.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">Among the dunes and wind-scoured rocky plains,
isolated pockets of hardy vegetation grow, flower and set seed. The
seeds attract sand grouse and roving bands of migrant finches.
Dainty gazelles known as “Mhorro” (<i>Nanger dama mhorr</i>)
which are critically endangered elsewhere in the Sahel, still graze
there, and the almost-mythical white antelopes (<i>Addax
nasomaculatus)</i> - one of the rarest hoofed animals in the world
and until recently thought to be extinct in the wild, are also to be
found... if you know where to look.</span></span></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-F8PNyb1wHTU/VJmlza27PpI/AAAAAAAAAoI/8SdwKCzeO4c/s1600/wsahara_lge11.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://2.bp.blogspot.com/-F8PNyb1wHTU/VJmlza27PpI/AAAAAAAAAoI/8SdwKCzeO4c/s1600/wsahara_lge11.jpg" height="215" width="400" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span>
</div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">The reason for all this
is the presence of s<i>ebkhets</i>.</span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">A <i>sebkhet</i> is
(in this context) a low-lying area where groundwater from aquifers
below the desert seeps to the surface. They can be brackish or can
contain fresh water, depending on the local geology. The mendicant
camel-drivers have always known about them and some of the larger,
more permanent ones have Arabic names. Others are smaller: they can
last for only a few years or even months, before the desert wind
covers them with sand again and exposes some other <i>sebkhet</i>
elsewhere.</span></span><br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.wildaddax.org/addax_nasomaculatus-1357505194.jpg" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="http://www.wildaddax.org/addax_nasomaculatus-1357505194.jpg" height="213" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: x-small;">Addax <span style="font-family: Verdana,sans-serif;">nasomaculatus (Image: wildaddax.org)</span></span></i></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">Ground-reflectance
images from satellites, together with LIDAR measurements, have
enabled scientists to map the distribution and extent of the desert
<i>sebkhets</i>. There are many more of these features than was
originally thought, and it is now clear that they are the secret of how
large grazing mammals have been able to survive in a place where none
should be. At the <a href="http://www.maroc-trip.com/Visiter-Voyage/790-Dakhla-Le_parc_national_de_Safia">Parc
National de Safia</a>, a closed reserve as been established where the
Mhorro and Addax are protected. Their numbers and gene pool have
been bolstered with captive-bred animals from European zoos, and the
last count was up 23% overall since the project started.</span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">In UV's area, there is
a permanent <i>sebkhet</i> and several small un-named ones. Perhaps
it isn't such a dull place for an osprey after all!</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="color: #660000;">[Sources:]
</span></div>
<span style="color: #660000;">
</span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="color: #660000;"><i>Directory of African
Wetlands</i>, R. H. Hughes, J. S. Hughes, G. M. Bernacsek<br /><i>Antelopes:
West and Central Africa – action plan</i>, R. East, ed. (WWF)</span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="color: #660000;"><i>Wild addax website</i>:</span> <a href="http://www.wildaddax.org/description.html">http://www.wildaddax.org/description.html</a> </div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com0tag:blogger.com,1999:blog-2053308650053762238.post-16893530617949879312014-12-21T14:08:00.000+00:002014-12-21T15:30:44.640+00:00Review: "Ospreys in Wales" by Emyr Evans<div class="western" style="margin-bottom: 0cm;">
<a href="http://1.bp.blogspot.com/-6cj2BXSpfnQ/VJbRr5M0e_I/AAAAAAAAAn4/UQztmkpkKXo/s1600/OIW_vert_800_1a.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" src="http://1.bp.blogspot.com/-6cj2BXSpfnQ/VJbRr5M0e_I/AAAAAAAAAn4/UQztmkpkKXo/s1600/OIW_vert_800_1a.jpg" height="320" width="220" /></a><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">This is not your
average bird book. <b> <i>Ospreys in Wales – the First Ten Years</i></b>
by Emyr Evans recounts a remarkable conservation success story –
but it is far more than that. At its very core, this is a book about
faith and inspiration, and about how the combination of these rather
abstract concepts brought about the re-establishment in Wales of
these rare and charismatic birds of prey.</span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">It is at once a
history, a memoir - and a thriller, with all the attributes required:
excitement, jeopardy, sex and violence, rivalry, betrayal, tragedy -
and flounders. (Though not necessarily in that order.) After an
erudite - and lavishly illustrated - introduction has set the scene,
Evans expands and develops the story. He writes in an easy,
conversational style that seamlessly draws the various locations and
events together. Eventually the birds themselves take centre stage,
as larger-than-life characters in their own dynastic saga – the
<i>englynion</i> of ospreys.</span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">There is plenty here to
delight the enthusiast, but the casual reader too is in safe hands.
Evans successfully avoids the twin pitfalls of anthropomorphism on
the one hand, and dry ascetics on the other. Instead, we are treated
to a narrative that carries us along into the fascinating world of
ospreys. Details and anecdotes abound, to be sure, but they are
presented lightly and with the author's own passion for his subject
shining through. Nor is his sense of humour (familiar to all of us
who know him) absent, though here it is suitably reined in.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">Emyr
Evans is a behavioural ecologist by training, but he is also a
photographer of rare skill with a sure eye for composition and
effect. <i>Ospreys in Wales</i> would be significant for its text
alone but the crowning glory of this hardback edition is the stunning
collection of colour plates that adorn and inform every page.
Drawing on his own library - as well as contributions from
professional Andy Rouse and others - Evans shows us why tens of
thousands of people around the world now follow every move that these
birds make.</span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">This is a true expert's
story, expertly and compellingly told. Highly recommended.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><span style="color: #660000;">"Ospreys in Wales - the First Ten Years" E. Evans (2014) ISBN: </span></span></span><span style="color: #660000;">0993099009</span><br />
<br />
Amazon: <a href="http://www.amazon.co.uk/Ospreys-Wales-First-Ten-Years/dp/0993099009">http://www.amazon.co.uk/Ospreys-Wales-First-Ten-Years/dp/0993099009</a><br />
<br />
Website: <a href="http://www.ospreysinwales.com/">http://www.ospreysinwales.com/</a></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com1tag:blogger.com,1999:blog-2053308650053762238.post-24773467545349071032014-12-14T16:13:00.000+00:002014-12-14T16:20:10.932+00:00Ghost Town<div class="western" style="margin-bottom: 0cm;">
</div>
<div class="western" style="margin-bottom: 0cm;">
</div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: large;">Geography lessons from
Ospreys #437</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Times,"Times New Roman",serif;"><i>Location: “Puntillas
de las Raimas”, Cintra, Western Sahara, N 23.08, W 16.20</i></span><br />
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
</div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">Kielder osprey “Blue
UV” arrived at the Gulf of Cintra on 11<sup>th</sup> December 2014
after an epic 2000 km migration flight from his long stopover in
southern Portugal. We were intrigued – few if any <i>tracked</i> birds have ever visited this remote and disputed spot on the edge of
the Sahara Desert. As UV looked around his new discovery, I did the
same thing on Google Earth. I knew almost nothing about it. Were
there any signs of human habitation around the place? There were
not.</span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">But there used to be...</span></span></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-XSOnrQdQE0E/VI1n9wwY9MI/AAAAAAAAAno/BRH04JtGUzA/s1600/cintra_gone1a.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://4.bp.blogspot.com/-XSOnrQdQE0E/VI1n9wwY9MI/AAAAAAAAAno/BRH04JtGUzA/s1600/cintra_gone1a.jpg" height="400" width="371" /></a></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span><br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span>
</div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">Separated in time by
nine years, these two aerial photographs of the same location show
that there was once a thriving fishing community here at Las Raimas.
Now the hundreds of boats - rough-built inshore craft known as
<i>piroques </i>- are gone, and the shanty town that housed their
owners and crews is almost buried under the shifting coastal sand
dunes. The bay is in a prime position for fishing (and for migrating
ospreys) located as it is in the middle of one of the most productive
continental shelves on the entire planet. The lee side of the bay is
an ideal haul-out for these shallow-draft boats as it is sheltered
from the prevailing northerly winds and the powerful Atlantic surf.
So what caused these people to abandon their village during this
period?</span></span><br />
<br />
<div class="western" style="margin-bottom: 0cm;">
</div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">It could have been the
local security situation: Western Sahara (formerly Spanish Sahara)
has seen sporadic armed conflict for years, victim to the rivalries
of its more powerful neighbours: Morocco, Mauritania and Algeria.
All of them have coveted its natural resources, but none of them have
done its people much good.</span></span><br />
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">Perhaps it was the encroachment of
the desert itself, or a failure of the (never reliable) water supply,
or the attractions of a less-hazardous way of life in some other
line of work. But I don't think it was any of these factors...</span></span></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-j256pG4LvMs/VI1n4r4y2YI/AAAAAAAAAnY/lJ1aUHw8cEk/s1600/Maartje%2BTheadora.jpg" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="http://1.bp.blogspot.com/-j256pG4LvMs/VI1n4r4y2YI/AAAAAAAAAnY/lJ1aUHw8cEk/s1600/Maartje%2BTheadora.jpg" height="212" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: xx-small;"><i><span style="font-family: Times,"Times New Roman",serif;">The German-registered super trawler "Maartje Theadora" operating off the<br />coast of Mauritania, 2013. (Greenpeace)</span></i></span></td><td class="tr-caption" style="text-align: center;"></td><td class="tr-caption" style="text-align: center;"></td><td class="tr-caption" style="text-align: center;"><span style="font-size: xx-small;"><i><span style="font-family: Times,"Times New Roman",serif;"></span></i></span><br /></td><td class="tr-caption" style="text-align: center;"></td><td class="tr-caption" style="text-align: center;"><span style="font-size: xx-small;"><i><span style="font-family: Times,"Times New Roman",serif;"></span></i></span><br /></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">In recent years, the
traditional artisan fishing industry in west Africa has been taking a
hammering. Locally-owned fish processing stations have closed, boats
have been laid up, whole coastal communities have been displaced.
The hammering has been administered by large foreign factory trawlers
from Europe, from Russia, and now from the Far East as well.
Operating around the clock - and on a netting scale that the <i>piroques</i>
cannot match - they can take out in one single day, more tonnage than
all the fishermen of Cintra would have harvested in their entire
season.</span></span><br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">The big trawlers need
nothing from the land, except fuel oil. They process and refrigerate
their own catch, and do not need to sell it at local markets. They
respect neither national agreements nor quotas, nor the boundaries of
marine reserves. The discarded by-catch includes every creature that
swims, and it all goes back over the side – dead. For the
countries affected, it's an economic and environmental disaster. But
down along the same coast, one man has had enough.</span></span><br />
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<a href="http://3.bp.blogspot.com/-PxqZYczmMss/VI1n5Gb1_PI/AAAAAAAAAnc/LcOGtvv61Nc/s1600/haidar_el_ali1.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="http://3.bp.blogspot.com/-PxqZYczmMss/VI1n5Gb1_PI/AAAAAAAAAnc/LcOGtvv61Nc/s1600/haidar_el_ali1.jpg" height="182" width="320" /></a><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"> Haïdar el Ali is
Senegal's pugnacious and mercurial Minister for Fisheries. Since
moving from Environment - where last year he took on Big Timber with
devastating effect – he has revoked 29 foreign operating licences,
arrested and detained the Russian trawler<i> </i></span></span><i>Oleg Naydenov</i><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">, and is
personally overseeing regeneration projects among his country's
artisan fishing communities. You can read more about his exploits
<a href="http://www.theguardian.com/global-development/2014/feb/26/senegal-fisheries-minister-foreign-factory-ships">HERE</a>.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">But what then for Las
Raimas? Its people may have moved elsewhere, but they will have taken
their disturbance and their pollution elsewhere, too. The lagoon at
the north side of the bay - known as the <i>Bajo Tortugo</i> ('little
tortoise', after the curiously-domed sandbar that guards its seaward
entrance) is now clean and quiet. At least one osprey has come there
instead for a visit. And he has come to a very remarkable place,
because the Gulf of Cintra is not just blue ripples and an empty beach:
its warm shallow waters are thought to be a nursery area for rare
marine life and mammals, including Risso's dolphins and the
critically-endangered Mediterranean monk seal. With suitable
research and protected status, it could be as important to the
eastern Atlantic ocean as the Sea of Cortez is to the Pacific.</span></span><br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"> I didn't know any of
this before UV arrived in the area, but I do now. He is doing a
great job.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /><span style="color: #660000;">LINKS:</span></span></span><br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><span style="color: #660000;">Forestry Commission England, Kielder osprey blog: </span><a href="https://kielderospreys.wordpress.com/" target="_blank">https://kielderospreys.wordpress.com/</a><br /><span style="color: #660000;">EU fisheries policy in West Africa (Oli Brown 2009)</span><a href="http://hdr.undp.org/sites/default/files/hdr2005_oli_brown_29.pdf" target="_blank"> http://hdr.undp.org/sites/default/files/hdr2005_oli_brown_29.pdf</a></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><span style="color: #660000;">Biodiversity - Atlantic coastal desert: (WWF) <a href="http://www.worldwildlife.org/ecoregions/pa1304">http://www.worldwildlife.org/ecoregions/pa1304</a></span></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
</div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com3tag:blogger.com,1999:blog-2053308650053762238.post-86862147235263528612014-12-07T13:31:00.000+00:002014-12-07T18:22:35.453+00:00The Migration Merry-go-Round<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;"><span style="font-size: large;"><span style="font-family: Times,Times New Roman,serif;"><i><b><span style="color: blue;">Migration
in Detail - (Part 3)</span></b></i></span></span> </span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">Way back in 1999, I
knew even less about ospreys than I do now. But I <u>did</u> know
some things about birds and I had completed my foundation course in
Meteorology, so when the Rutland translocation project came to my
attention, I – and many other enthusiasts – followed its progress
with increasing fascination. Some of the translocated juveniles were
fitted with tracking devices. In those days, the units were
primitive and highly experimental: they used ARGOS doppler signalling
to calculate the positional fixes (which we now know to be a
less-than-ideal method.) The trackers were as unreliable and
short-lived as a politician's election promises – and only
marginally more accurate. But they worked.<br /><br />When one of the
birds, a male tagged as <a href="http://www.zen88810.zen.co.uk/ROspreys%20site/BirdRO3.htm">R03(1999)</a>,
showed some unexpected course deviations over the Sahara Desert, I
suggested that he was avoiding a formation of adverse weather systems
(which I had detected on weather satellite images) that had developed
to the south-west of his position, and that these might affect his
ability to use soaring flight while over the desert. This suggestion
was put to the Men Who Knew A Lot About Ospreys at the next group
meeting. It was not favourably received.</span></span><br />
<br />
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">“<i>Ospreys on
migration use thermals very little, if at all”</i> was the
conclusion of the MWKALAO, although they didn't offer any alternative
theory to explain the bird's behaviour. Being a humble and
uninformed amateur, I accepted this as being the expert view...</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">Until now</span></span><br />
<br />
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">When the published
track from Finnish osprey “Helena” came in for early October
2014, it seemed to show that here again was a bird using soaring
techniques while over the desert.</span></span></div>
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-8UIVZOaFvL4/VIRRnTVR5WI/AAAAAAAAAm0/XNe-4D1lMKg/s1600/helena_thermals1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://2.bp.blogspot.com/-8UIVZOaFvL4/VIRRnTVR5WI/AAAAAAAAAm0/XNe-4D1lMKg/s1600/helena_thermals1.jpg" height="228" width="400" /></a></div>
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">Unlike the examples I
produced for previous articles in this series, Helena's sample is not
“slope soaring” or any other kind of terrain-following flight.
There are no slopes at this point, no escarpments or ridges to
provide an updraught. To me, these movements looked very like direct
thermal altitude modification. But it was not quite conclusive. To
be absolutely certain, I needed to get my hands on the actual data
files for an osprey flying over Europe (where there are lots of GSM
cell towers) so that the recorded level of detail was as high as
could be possible with this new technology. </span></span></div>
<br />
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">Joanna Dailey, who
volunteers with the <a href="https://kielderospreys.wordpress.com/location-maps/">Forestry
Commission osprey conservation project at <table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-czGjGGGTSU4/VIRRqRDDtVI/AAAAAAAAAnE/vN3R0ZEwE0w/s1600/VV_nest_FC_a22.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="http://1.bp.blogspot.com/-czGjGGGTSU4/VIRRqRDDtVI/AAAAAAAAAnE/vN3R0ZEwE0w/s1600/VV_nest_FC_a22.jpg" height="203" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: xx-small;"><i>Blue VV at nest Aug 2014. Blue UV in the background<br />(Image: Forestry Commission England)</i></span></span></td></tr>
</tbody></table>
Kielder Forest</a>,
arranged for me to get authorised copies of their files for three
juveniles. They were carrying GSM trackers and all were operating
correctly. The hunt was on.</span></span><br />
<br />
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">Two of Kielder's birds
followed a mainly coastal and/or over-sea route for their migration.
But the third, tagged as “Blue VV”, migrated over land and
through central Spain. With light winds and hot sun in late summer,
this is prime territory for the formation of thermals. Each day I had
been carefully saving the weather charts for this region and these
told me exactly when and where to look for the evidence. And little
VV did not disappoint me.</span></span><br />
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-jDYJptkJqCc/VIRRpMqnx4I/AAAAAAAAAm8/Ds2f9sup6sw/s1600/vv_thermal_spain1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://4.bp.blogspot.com/-jDYJptkJqCc/VIRRpMqnx4I/AAAAAAAAAm8/Ds2f9sup6sw/s1600/vv_thermal_spain1.jpg" height="216" width="320" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;"></span></span>
</div>
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">Even position fixes at
70 seconds apart does not conclusively prove that spiralling flight
has taken place – but adding in the direction of travel at each
data point <u><i>does</i></u>. During this afternoon flight, there are
eight other examples of the same behaviour, roughly at even time
intervals.</span></span><br />
<br />
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">So... were the Men Who Knew A Lot About Ospreys
wrong, fifteen years ago? Well, not really, but they may have been
misled by the early technology which - given the comparatively low
number of cumulative fixes - seems to show birds flying in
reassuringly straight lines across the broader landscape, when in
fact they do nothing of the sort. As I have tried to show in this
series, we are still learning things about the minutiae of bird
migration...</span></span><br />
<br />
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">… and there's a lot more yet to be discovered.</span></span><br />
<br />
<span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-size: small;">In the final part of
this series, we will consider the physiology and layout of raptor
wings, and see how evolution has adapted different species to have
the appropriate “equipment” for their varying
lifestyles.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="color: #660000;"><span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: small;"><br /><i>Wildlifewriter acknowledges the use
of tracking data supplied by the Natural History Museum of Finland
</i><i><span style="text-decoration: none;">(</span></i><span style="text-decoration: none;">Luonnontieteellinen
Keskusmuseo</span><i><span style="text-decoration: none;">)</span></i><i>and the Finnish Osprey Foundation, and data and images by Forestry
Commission England.</i></span></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: x-small;"><i><span style="font-size: small;"><b>Links:</b></span><br /><br />Rutland Water Translocation History: <a href="http://www.ospreys.org.uk/osprey-facts/the-translocation-project/">http://www.ospreys.org.uk/osprey-facts/the-translocation-project/</a></i></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: x-small;"><i>Kielder Osprey Blog (Joanna Dailey): <a href="https://kielderospreys.wordpress.com/">https://kielderospreys.wordpress.com/</a></i></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: x-small;"><i></i></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: x-small;"><i></i></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: x-small;"><i></i></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: x-small;"><i>Bird's Soaring flight (Technical): <a href="http://arxiv.org/ftp/arxiv/papers/1012/1012.0434.pdf">http://arxiv.org/ftp/arxiv/papers/1012/1012.0434.pdf</a><br /> </i></span></div>
<span style="font-size: x-small;">
</span>Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com0tag:blogger.com,1999:blog-2053308650053762238.post-33195511871637923472014-11-22T15:24:00.000+00:002014-11-22T17:07:27.661+00:00Slope Soaring and Ridge Riding<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Times, Times New Roman, serif;"><span style="font-size: large;"><i><b><span style="color: blue;">Migration
in Detail - (Part 2)</span> </b></i></span></span>
</div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">In the <a href="http://thewildlifewriter.blogspot.co.uk/2014/10/downwind-tacking.html">previous
article in this series</a>, we looked at one of the energy-saving
flight modifications used by ospreys and other raptors during their
migrations. Like human glider pilots, ospreys have developed a whole
range of techniques that can be used - either singly or in
combination – to gain maximum advantage from the prevailing
conditions.</span></span></div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"><br /></span></span>
</div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">Using data from the
latest GSM-type tracking units, which can log flight parameters at
intervals of minutes - rather than hours, as was typical of the older
UHF devices – we can get a much clearer view of what these birds
are doing and how they are doing it...</span></span></div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"><br /></span></span>
</div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
<div class="separator" style="clear: both; text-align: center;">
<a href="http://3.bp.blogspot.com/-xwAEJZtf29E/VHCo3eM6qBI/AAAAAAAAAmg/DyUN-eFA3sc/s1600/tero_slopesoar1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://3.bp.blogspot.com/-xwAEJZtf29E/VHCo3eM6qBI/AAAAAAAAAmg/DyUN-eFA3sc/s1600/tero_slopesoar1.jpg" height="228" width="400" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">In November 2014, adult
male osprey “Tero” was flying south-west down the Arabian
Peninsula. After a major diversion to avoid adverse weather south of
Iraq, he had reached the <i>Jabal Tuwayq</i> - a long north-south
escarpment that marks the eastern boundary of the <i>Asir</i>
Highlands in Saudi Arabia. The winds were light but slightly against
him. But Tero was able to use the overall rising air current caused
by the gentle terrain gradient in a method known to pilots as “slope
soaring”</span></span></div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span><span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span><br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"> </span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<a href="http://2.bp.blogspot.com/-fObk_QLu8_Q/VHCozf_9TwI/AAAAAAAAAmM/ZxbT0tSMYQs/s1600/soar_diagr1.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="http://2.bp.blogspot.com/-fObk_QLu8_Q/VHCozf_9TwI/AAAAAAAAAmM/ZxbT0tSMYQs/s1600/soar_diagr1.jpg" height="167" width="320" /></a><span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">As with the “crosswind
tacking” technique, this allowed him to gain altitude by turning UP
the slope, and then maintain course progress by flying down it at a
shallower angle. The advantage of this system is that it works for
almost any wind direction that is at a greater angle to the line of
slope than 30 degrees.</span></span></div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"><br /></span></span>
</div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="http://4.bp.blogspot.com/-4V9QjyUqnFk/VHCo00ysUrI/AAAAAAAAAmU/KeabWPhBY6k/s1600/_7H.jdIMG_1461.jpeg" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="http://4.bp.blogspot.com/-4V9QjyUqnFk/VHCo00ysUrI/AAAAAAAAAmU/KeabWPhBY6k/s1600/_7H.jdIMG_1461.jpeg" height="260" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: xx-small;"><span style="font-family: Times,"Times New Roman",serif;">"Blue 7H" (Image: Joanna Dailey)</span></span></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">A variant of this
flight mode is what I've chosen to call “ridge riding”. It is an
adaptation to more complex upland terrain where there are many
changes of elevation, with steep-sided river valleys and hill crests.
And the example chosen this time features “Blue 7H” - a female
first-time migrant from nest #2 at Kielder Forest. Blue 7H provides
the possible answer to a question that came up on one of the
discussion groups, which (in summary) was:<br /><br /><b><i>“Do juvenile
birds have the innate (instinctive) ability to use these
energy-saving techniques, or do they have to learn them as adults?”</i></b></span></span></div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"><br /></span></span>
</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://2.bp.blogspot.com/-zFyllbZ6ADA/VHCo24TsYQI/AAAAAAAAAmc/82KpoJDgBi8/s1600/7h_ridgeride1.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="" border="0" src="http://2.bp.blogspot.com/-zFyllbZ6ADA/VHCo24TsYQI/AAAAAAAAAmc/82KpoJDgBi8/s1600/7h_ridgeride1.jpg" height="218" title="Click for larger" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"><br /></span></span>
</div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;"></span></span>
</div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">Only seven days after
leaving her natal nest, 7H had reached the Galicia region of
northwest Spain. Crossing this mountainous and forested landscape,
she took advantage of local up-currents along the windward side of
ridges to maintain the necessary height and made good progress
southward and into Portugal. It seems like even a young bird of prey
comes equipped with the full repertoire of flight, and only needs to
add a modicum of practice. This confirms visual observations of
other migratory species on their first migrations.<br /><br />In the
final part of this series, we will look at some other flight modes
that are used by ospreys, and see how their anatomy and wing layout
influences what they are able to do.</span></span></div>
<span style="font-size: small;"><span style="font-family: Verdana,sans-serif;">
</span></span>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Times,"Times New Roman",serif;"><span style="color: #783f04;"><i>Wildlifewriter
acknowledges the use of tracking data supplied by the Natural History
Museum of Finland </i><i><span style="text-decoration: none;">(</span></i><span style="text-decoration: none;">Luonnontieteellinen
Keskusmuseo</span><i><span style="text-decoration: none;">)</span></i><i>and the Finnish Osprey Foundation, and data and images by Forestry
Commission England.</i></span></span></div>
<span style="font-family: Times,"Times New Roman",serif;"><span style="color: #783f04;">
</span></span>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<i>Links:</i></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<i>LUOMUS: <a href="http://www.luomus.fi/en">http://www.luomus.fi/en</a></i></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<i>Kielder Osprey Blog: <a href="https://kielderospreys.wordpress.com/">https://kielderospreys.wordpress.com/</a></i></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com1tag:blogger.com,1999:blog-2053308650053762238.post-28404643878991779412014-11-10T17:45:00.000+00:002014-11-11T13:03:22.571+00:00A Goldfish for Birgit<div class="separator" style="clear: both; text-align: left;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">If I could, I would
travel to Senegal, find “Birgit” the osprey, and hand her a
halibut in person. And not just any halibut, but a halibut made of
solid gold and inlaid with semi-precious stones.</span></span><span style="font-size: small;"><a href="http://1.bp.blogspot.com/-V6dkecjr414/VGD3KtgAAgI/AAAAAAAAAlU/4RHQrUwaVLs/s1600/goldhalibut.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="http://1.bp.blogspot.com/-V6dkecjr414/VGD3KtgAAgI/AAAAAAAAAlU/4RHQrUwaVLs/s1600/goldhalibut.jpg" height="240" width="320" /></a></span></div>
<div style="text-align: left;">
</div>
<div style="text-align: left;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<i><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></i>
</div>
<i><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span></i>
<br />
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><i>Which she probably
wouldn't like.</i><br /> </span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">I don't actually have the money or the time (or
indeed, a golden halibut) for such an extravagant gesture but the
reward would not be unfitting. Not since the time of Ceulan himself
has there been such an osprey for the getting of knowledge – and
the stories of these two remarkable young birds intersect in a way
that could not have fallen out better if I had dared to script it
myself... <br /><br />There are many scientific theories about how
long-distance migratory birds achieve their point-to-point
navigation. The current wisdom (such as it is) involves a synthesis
of various sensory contributions and, over the years, several studies
have suggested that birds can “see” the Earth's magnetic field in
order to orient themselves. The results have been mixed (to say the
least!) and often non-repeatable – which, in Science, is generally
A Bad Thing.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-9WK_mWXamfc/VGD3MbsGzII/AAAAAAAAAls/wfWU490fxN0/s1600/keiet_far_1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://4.bp.blogspot.com/-9WK_mWXamfc/VGD3MbsGzII/AAAAAAAAAls/wfWU490fxN0/s1600/keiet_far_1.jpg" height="174" width="320" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">The proponents of magnetic navigation have had to
take their idea through several iterations: originally it was
proposed that birds – and other animals – had some kind of
“built-in compass” that told them which way was North. This ran
into trouble quite quickly, when experiments showed that animals have
no concept of “North” as a specific direction. The next version
was that these creatures were obtaining positional information from
lines of magnetic force. Unfortunately, this doesn't work very well
either: in many places on its surface, the Earth's magnetic field
lines lie parallel to each other, which would make them useless for
point location.<br /><br />To get round this problem, the next
modification was that animals could sense the “inclination” of
field lines – sometime referred to a the “dip angle” which
changes with both latitude and longitude. This is certainly feasible
(in theory) but even us humans need extremely sophisticated and
accurate instruments to measure the dip variation - which is very
small – and there was no known sensory apparatus in birds that
would be capable of doing this. Meanwhile, researchers who actually
<b>know</b> something about birds were studying data from tracking
experiments and ring recoveries.[1] In Sweden, an important study
looked for the characteristic direction shift that would be evidence
of such a navigational mechanism. They did not find it.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span><br />
<div class="separator" style="clear: both; text-align: center;">
</div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">The magnetophiles did
not give up. Microscopic particles of iron oxide were found in
birds' beaks, in the their eyes, their brains, and even in their
feet! Weird quantum-mechanical effects were invoked [2] although
with a convenient disregard for the actual laws of Quantum Physics.
Some experiments were done which were so creative that no animals
were involved in them at all. The debate continues and the jury is
still out on this stuff.<br /><br />So – at least as far as ospreys and
other raptors are concerned – where does the evidence lie? Is this
whole “magnetic navigation” thing the genuine banana, or just a load
of haphazard hornswoggle? Can't the birds themselves help us out
with this?<br /><br /><i>Oh yes...</i></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-40yXFa2FG40/VGD3L-no7AI/AAAAAAAAAlk/JqkjTt1o9gE/s1600/kediet_osps_migr2.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://1.bp.blogspot.com/-40yXFa2FG40/VGD3L-no7AI/AAAAAAAAAlk/JqkjTt1o9gE/s1600/kediet_osps_migr2.jpg" height="223" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">[Click for larger]</td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><i> </i><br />When Ceulan made his epic
migration in September 2012 he passed right over the Kediet al Jill –
a 500m-high “guelb” or outcrop hill of magnetite iron ore in
eastern Mauritania. This place is one of the most prominent and
highly-localised magnetic anomalies anywhere on Earth so if Ceulan's
navigational sense was ever going to be visibly affected by anything,
this is the place where it would happen.</span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-qHiS6nvt-XM/VGD3KpDN2EI/AAAAAAAAAlY/NblEy7wM1rE/s1600/cuulan_flies1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://4.bp.blogspot.com/-qHiS6nvt-XM/VGD3KpDN2EI/AAAAAAAAAlY/NblEy7wM1rE/s1600/cuulan_flies1.jpg" height="220" width="320" /></a></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">His course did not
deviate by any appreciable amount. But THAT was only one example –
until last week, when Birgit came to the same place. (4.11.2014) Not
content with a simple pass-by demonstration, she roosted for the
night on the north-west slope of the mountain itself. And in the
morning, the time when all ospreys take their bearings and direction
for the coming day's flight, she simply took off and headed straight
towards her eventual wintering site in northern Senegal.<br /> </span></span><br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">If ospreys really <u>did</u> use field lines as a primary navigation method, both of these birds would have been flying in circles around the Kediet until they got far enough away from it. But there is no sign that it had any effect on their navigation whatsoever.<br /><i></i></span></span><br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><i></i></span></span><br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><i>Magnetic
beaks, my ass...</i></span></span><a href="http://2.bp.blogspot.com/-SBQiqL5vzec/VGD3MbB4r2I/AAAAAAAAAlo/yXsrgISk_lc/s1600/smilieface1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://2.bp.blogspot.com/-SBQiqL5vzec/VGD3MbB4r2I/AAAAAAAAAlo/yXsrgISk_lc/s1600/smilieface1.jpg" /></a></div>
<span style="font-size: small;"><i> </i><br /><br />-Wlw.</span><br />
<br />
<span style="font-size: small;"><span style="font-size: large;"><span style="font-family: Times,"Times New Roman",serif;"><span style="color: #660000;"><i>Wildlifewriter
acknowledges the use of tracking data supplied by Montgomeryshire Wildlife Trust, the Natural History
Museum of Finland </i><i><span style="text-decoration: none;">(</span></i><span style="text-decoration: none;">Luonnontieteellinen
Keskusmuseo</span><i><span style="text-decoration: none;">)</span></i></span><i><span style="color: #660000;">
and the Finnish Osprey Foundation.</span></i></span></span></span>
<br />
<br />
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span>
</div>
<span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="color: blue;"><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">[1]<i> </i><i><span style="font-weight: normal;">“Satellite
tracking of Swedish Ospreys </span></i><span style="font-style: normal;"><span style="font-weight: normal;">Pandion
haliaetus</span></span><i><span style="font-weight: normal;">:
autumn migration routes and orientation”</span></i>
Mikael
Hake, Nils Kjellén and Thomas Alerstam, J<i>OURNAL
OF AVIAN BIOLOGY 32: 47 – 56. Copenhagen 2001</i></span></span></span></div>
<span style="color: blue;"><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="color: blue;"><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;"><br /></span></span></span>
</div>
<span style="color: blue;"><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">
</span></span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="color: blue;"><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">[2] “<a href="http://www.ks.uiuc.edu/Publications/Papers/abstract.cgi?tbcode=SCHU78C"><i><span style="text-decoration: none;">A
biomagnetic sensory mechanism based on magnetic field modulated
coherent electron spin motion</span><span style="text-decoration: none;">.</span></i></a><i>”</i> Klaus
Schulten, Charles E. Swenberg, and Albert Weller. </span></span><i><span style="font-family: Verdana,sans-serif;"><span style="font-size: small;">Zeitschrift
für Physi</span></span>kalische Chemie</i>, NF111:1-5, 1978</span></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com1tag:blogger.com,1999:blog-2053308650053762238.post-29140703485323168672014-10-27T12:38:00.001+00:002014-10-27T12:39:29.601+00:00Downwind Tacking<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: large;"><span style="font-family: Times,"Times New Roman",serif;"><i><b><span style="color: blue;">Migration in Detail - (Part 1)</span> </b></i></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<div style="text-align: left;">
<a href="http://3.bp.blogspot.com/-BynlLnCEPes/VE0cGhjkWQI/AAAAAAAAAlE/l1yD3vNlB7c/s1600/Seija%2B%2B%2BHarri%2B%2B%2BJoona_800x.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" src="http://3.bp.blogspot.com/-BynlLnCEPes/VE0cGhjkWQI/AAAAAAAAAlE/l1yD3vNlB7c/s1600/Seija%2B%2B%2BHarri%2B%2B%2BJoona_800x.jpg" height="240" width="320" /></a></div>
<div style="text-align: left;">
<span style="font-family: Times,"Times New Roman",serif;"></span><span style="font-size: x-small;"><span style="color: #134f5c;"><span style="font-family: Times,"Times New Roman",serif;">Image 1 - Osprey "Seija" being fitted with her PTT tracking unit by Harri & Joona Koskinen near her home nest in<b> </b>Utsjoki, Finland. Photo: Tero Niskanen. Used by permission, Osprey Foundation Sääksisäätiö, Finland</span></span></span></div>
<div style="text-align: left;">
</div>
</div>
<div class="western" style="margin-bottom: 0cm;">
<div style="text-align: left;">
</div>
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; text-align: right;"><tbody>
<tr><td style="text-align: center;"><img border="0" src="http://1.bp.blogspot.com/-sIDg0iOd5NA/VEt4GQrFBgI/AAAAAAAAAkQ/mLPRQ_BRBuI/s1600/vor_sailplan1.jpg" height="320" style="margin-left: auto; margin-right: auto;" width="212" /></td></tr>
<tr align="left"><td class="tr-caption"><span style="color: #0b5394;"><span style="font-size: xx-small;">The new VO65 yacht has a high aspect-<br />ratio sail plan, suitable for trans-ocean <br />endurance racing</span></span></td></tr>
</tbody></table>
<span style="font-size: small;">On the 11<sup>th</sup>
October, the competitors in the 2014/15 Volvo Ocean Race departed
Alicante on the first leg of their 70,000km round-the world voyage.
They left the Mediterranean and, three days later as they were
heading down the coast of Morocco, the wind was directly behind them.
This was no good at all, and something had to be done.</span><br />
<br />
<span style="font-size: small;"><span style="font-size: small;">The class of sailing
boats being used – the Volvo Ocean 65 – is no luxury cruising
yacht. They are cramped, noisy, uncomfortable, wet, overpowered and
undermanned – and ridiculously fast. Despite being over 20m long,
the VO65 weighs less than 13 tonnes. It is constructed from carbon
fibre and other lightweight composite materials. The sails are not
made from sewn cloth panels in the traditional way: instead, they are
vacuum formed from high-modulus fabrics such as Kevlar on an enormous
mould that creates an aerodynamic profile, like the wing of a bird. </span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<br />
<span style="font-size: small;"></span><span style="font-size: small;">Migrating ospreys are
in a kind of race, too. However, the rules for <i>their</i> contest
have been set by Evolution and the winners are those birds who
complete the set distance – not in the shortest time, but with the
least expenditure of energy. In order to do this, migrant birds seem
to have a number of strategies that they can choose from, depending
on the conditions encountered along their routes. And one of these
methods is very similar to a technique developed by the helmsmen of
modern high-performance racing craft:-<b> </b></span><br />
<br />
<span style="font-size: small;"><b>Downwind tacking.</b></span></div>
<div class="western" style="margin-bottom: 0cm;">
</div>
<span style="font-size: small;">
</span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-nglNwDQbcOY/VEt4TtLLx3I/AAAAAAAAAkc/p-Q1fz8ejl8/s1600/vor_downwind1.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" src="http://4.bp.blogspot.com/-nglNwDQbcOY/VEt4TtLLx3I/AAAAAAAAAkc/p-Q1fz8ejl8/s1600/vor_downwind1.jpg" height="153" width="320" /></a></div>
<span style="font-size: small;"> No sailing vessel can
progress directly into the wind. Instead, they must steer a zig-zag
course at angles of about 30 degrees to the wind direction, making
several “tacks” - or changes of direction – to reach a given
point. Sailing directly AWAY from the wind is much easier but, for
these racing machines, it is very inefficient because the boat can
actually sail faster than the wind which propels it. The crews have
worked out that they can achieve a lower point-to-point elapsed time
(the velocity made good, or “VMG” for short) by sailing at
maximum speed, again at an angle to the wind. They cover a greater
distance, but the overall time taken taken to do so is improved.</span><br />
<br />
<span style="font-size: small;">Millions of years ago,
migratory birds discovered the same trick BUT, instead of optimising
speed (VMG), they adapt to the conditions and achieve maximum
<i>distance</i> per unit of energy expended. Unlike the yachtsmen,
birds find that a crosswind has a BAD effect on their flight
efficiency, and this is for two reasons: firstly because they have
to make constant small course corrections to stay on track, and
secondly because the airflow over their wings is disrupted, resulting
in excess drag due to turbulence.<br /><br />In autumn 2014, an adult
female osprey named “Seija” was fitted with a GSM satellite
tracker by researchers in northern Finland.<span style="font-size: xx-small;">[1]</span>
She migrated strongly down through Europe, crossed the Adriatic near
the “heel” of Italy and skipped over the widest part of the
Mediterranean in a single 14-hour hop. Rather than resting, Seija
continued southwards during the next day before coming to roost at
the edge of the Lybian desert. She had flown 5300 km in only thirty
days.<br /><br />Next morning, Seija was up and flying early and within
three days had reached the border between Algeria and Niger. How was
she managing to cover these distances, across the wind? The chart
below shows the details of one hour's flying time, and illustrates
that these adult ospreys from Finland know a thing or two about
crossing deserts...</span></div>
<span style="font-size: small;">
</span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://4.bp.blogspot.com/--fvtVJFNodY/VEt7AuoWh8I/AAAAAAAAAk0/paKCrmywpKI/s1600/seija_tacking_oct2014.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://4.bp.blogspot.com/--fvtVJFNodY/VEt7AuoWh8I/AAAAAAAAAk0/paKCrmywpKI/s1600/seija_tacking_oct2014.jpg" height="215" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="color: #0b5394;">[Click for larger]</span></td></tr>
</tbody></table>
<span style="font-size: small;"></span>
</div>
<span style="font-size: small;">So what is going on
here? The figures in white are altitude (in metres) at each track
point where there is a major direction change, and the points
themselves are registered at intervals of about 80 seconds. There is
no cloud cover. The land surface is about 600m and comprises flat
stony desert terrain, with some low-growing scrub vegetation in
patches. There are no large-scale thermals here, because the area is
dominated by stable high pressure. <i>However</i>, small columns of
rising air form locally in the surface layer, and these can be very
numerous as the terrain is heated unevenly by direct sunlight. </span><br />
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<div class="separator" style="clear: both; text-align: center;">
<a href="http://3.bp.blogspot.com/-mWX1qKQILV8/VEt4TgXb1bI/AAAAAAAAAkY/AsxkFYv0pSg/s1600/seija_graph1.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" src="http://3.bp.blogspot.com/-mWX1qKQILV8/VEt4TgXb1bI/AAAAAAAAAkY/AsxkFYv0pSg/s1600/seija_graph1.jpg" height="183" width="320" /></a></div>
<span style="font-size: small;"> Each
time Seija encounters one of these, she turns downwind and uses it to
gain height. Her rate of climb is around 200 metres per minute –
probably achieved with little or no extra effort AND without wasting
time on “classical” spiral soaring. Seija simply flies in the
up-current while it lasts. As soon as she reaches the limit of the
column, she turns back on her proper course, flying easily with
occasional wing-flaps – not gliding, but gradually losing altitude
to increase speed and conserve energy. Clever Seija is experienced
at this migration stuff and she knows that her path will soon cross
another up-current, where she can repeat the trick.</span><br />
<br />
<span style="font-size: small;">Adding up the figures
for this part of her journey, I find that Seija had covered a much
larger aggregate distance than a direct start-to-finish route, but in
much the same time as she would have done without employing this
technique. Meanwhile, back on the ocean, the VOR sailors had
achieved overall average speeds of 8.7 knots in a wind that rarely
blew over 10 knots. </span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><i><br />I bet they had to work a lot harder than
Seija did.</i></span><br />
<span style="font-size: small;"><i> </i></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
So... does all this
mean that ospreys never use soaring flight in thermals during
migration? No, it doesn't – and in the next part of this article,
we will take a look at a different bird in a different part of the
desert, some other variants of long-distance bird flight, and see how
an osprey's wing-shape is perfectly adapted for these purposes.</div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<div class="western" style="margin-bottom: 0cm;">
<br /></div>
<span style="font-size: small;">
</span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: large;"><span style="font-family: Times,"Times New Roman",serif;"><span style="color: #660000;"><i>Wildlifewriter
acknowledges the use of tracking data supplied by the Natural History
Museum of Finland </i><i><span style="text-decoration: none;">(</span></i><span style="text-decoration: none;">Luonnontieteellinen
Keskusmuseo</span><i><span style="text-decoration: none;">)</span></i></span><i><span style="color: #660000;">
and the Finnish Osprey Foundation.</span><br /><br /><span style="font-size: xx-small;">[1]</span> Links:-<span style="font-size: small;"> </span></i></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: large;"><span style="font-family: Times,"Times New Roman",serif;"><i><span style="font-size: small;">LUOMUS: </span></i><span style="font-size: small;"><a href="http://www.luomus.fi/en">http://www.luomus.fi/en</a></span></span></span><span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;"><span style="font-weight: normal;"><i> </i></span></span></span></div>
<h2>
<span style="font-size: small;"><span style="font-family: Times,"Times New Roman",serif;"><span style="font-weight: normal;"><i>Sääksisäätiö:</i> <a href="http://www.saaksisaatio.fi/en/index.htm">http://www.saaksisaatio.fi/en/index.htm</a></span></span></span><span style="font-family: Times,"Times New Roman",serif;"><span style="font-weight: normal;"><span style="font-size: small;"> </span></span></span></h2>
<h2>
<span style="font-family: Times,"Times New Roman",serif;"><span style="font-weight: normal;"><i><span style="font-size: small;">Volvo Ocean Race:</span></i><span style="font-size: small;"> <a href="http://www.volvooceanrace.com/en/home.html">http://www.volvooceanrace.com/en/home.html</a></span><br /> </span></span></h2>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: large;"><span style="font-family: Times,"Times New Roman",serif;"><i><br /></i></span></span></div>
<span style="font-size: small;"></span></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com2tag:blogger.com,1999:blog-2053308650053762238.post-34668760910172138152014-09-27T12:19:00.000+01:002014-09-27T13:05:38.874+01:00“BIRGIT" - a very useful osprey<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://2.bp.blogspot.com/-b6ZdGksoOZY/VCabdJuF5NI/AAAAAAAAAjs/WCgPt30PvZs/s1600/birgit_sept2014_GE.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://2.bp.blogspot.com/-b6ZdGksoOZY/VCabdJuF5NI/AAAAAAAAAjs/WCgPt30PvZs/s1600/birgit_sept2014_GE.jpg" height="225" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: xx-small;">Image: Google Earth. Data: LUOMOS Finland (University of Helsinki)<br />*West is up</span></td></tr>
</tbody></table>
<div class="western" style="margin-bottom: 0cm;">
</div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: large;"><i><span style="font-family: Arial,Helvetica,sans-serif;">What's the use of
satellite tracking, anyway?</span></i></span></div>
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">
</span></span>
<br />
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">It's a question that
regularly crops up on the non-science forums and social media sites.
Those who ask it often load the question with some opinion to the
effect that<i> “we already know where these birds spend the winter, so
what is the point of continuing to track them?” </i>But the birds
themselves provide the answer to this... </span></span><br />
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;"><br /></span></span></div>
<div class="western" style="margin-bottom: 0cm;">
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">Increasingly,
ecological research is getting down to the fine details of animal
behaviour: things that only advanced technologies – close-up
video cameras and microphones, and high-resolution data gathering –
can uncover. These days, and probably for the first time in history,
we are beginning to study bird behaviour in the wild on the scales at
which birds themselves operate. And the observations are
revealing.<br /><br />Osprey “Birgit” fledged from a nest in southern
Finland in August 2014 and, as part of a programme run by the Natural
History Museum of Finland, was fitted with a GSM datalogger /
transmitter unit. She duly migrated south-west over the Baltic and
decided to make a stopover near the Ijsselmeer in Holland. Birgit's
“2<sup>nd</sup> generation” tracker unit is able to record her
position, speed and altitude every two minutes, varying this sample
rate automatically according to her level of activity.<br /><br />Birgit
found that the flat fields and canals of the Dutch polder were much
to her liking, and began to hunt for fish there – probably the
first time in her young life that she had done this. The detailed
satellite tracking shows that Birgit has instinctively adopted the
usual foraging strategy for an osprey. She has some favourite trees
for roosting, but does not visit the same places every day to hunt
for fish. Instead, Birgit has prospected over a corridor that is
some 20km in length, from the towns of Lemmer in the north to beyond
Emmeloord in the south.<br /><br />The fact that even juvenile ospreys –
though not the most effective hunters, due to their inexperience –
do not repeatedly exploit a single food source is important
information, and Birgit has provided confirmation of it. In an
increasingly crowded world, people and wildlife can come into
conflict, and one charge often levelled at ospreys by the
recreational angling community is that they <i>“eat all the fish and
then move on, leaving none for us to catch.”</i> But this is wrong,
and the latest technological tools are helping conservationists to
prove it.</span></span></div>
<span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">
</span></span>
<br />
<div class="western" style="margin-bottom: 0cm;">
<b><span style="font-size: small;"><span style="font-family: Arial,Helvetica,sans-serif;">Birgit's autumn sojourn
in Holland is just as useful to us as it is (no doubt) to
her.</span></span></b><br />
<br />
<span style="font-family: Times,"Times New Roman",serif;"><span style="font-size: x-small;"><span style="color: #660000;">Links: Finland Museum of Natural History (in
English):<span style="color: blue;"> http://www.luomus.fi/en</span></span></span></span><br />
<span style="color: #660000;"><span style="font-size: x-small;"><span style="font-family: Times,"Times New Roman",serif;">Osprey “Birgit” tracking page: <span style="color: blue;">http://koivu.luomus.fi/info/tracking/index.php/mapper/map/panhal_birgit_autumn2014</span></span></span></span></div>
Wildlifewriterhttp://www.blogger.com/profile/13030875234714964301noreply@blogger.com0